diff --git a/src/AddIns/DisplayBindings/XmlEditor/Project/Src/XmlCompletionDataProvider.cs b/src/AddIns/DisplayBindings/XmlEditor/Project/Src/XmlCompletionDataProvider.cs
index 83fcc03080..dbe9c2ab03 100644
--- a/src/AddIns/DisplayBindings/XmlEditor/Project/Src/XmlCompletionDataProvider.cs
+++ b/src/AddIns/DisplayBindings/XmlEditor/Project/Src/XmlCompletionDataProvider.cs
@@ -63,9 +63,11 @@ namespace ICSharpCode.XmlEditor
 					
 				case ' ':
 					// Attribute intellisense.
-					XmlElementPath path = XmlParser.GetActiveElementStartPath(text, text.Length);
-					if (path.Elements.Count > 0) {
-						return GetAttributeCompletionData(path);
+					if (!XmlParser.IsInsideAttributeValue(text, text.Length)) {
+						XmlElementPath path = XmlParser.GetActiveElementStartPath(text, text.Length);
+						if (path.Elements.Count > 0) {
+							return GetAttributeCompletionData(path);
+						}
 					}
 					break;
 					
diff --git a/src/AddIns/DisplayBindings/XmlEditor/Project/Src/XmlParser.cs b/src/AddIns/DisplayBindings/XmlEditor/Project/Src/XmlParser.cs
index e47f895ec3..56905da151 100644
--- a/src/AddIns/DisplayBindings/XmlEditor/Project/Src/XmlParser.cs
+++ b/src/AddIns/DisplayBindings/XmlEditor/Project/Src/XmlParser.cs
@@ -145,9 +145,7 @@ namespace ICSharpCode.XmlEditor
 				return false;	
 			}
 			
-			if (index >= xml.Length) {
-				index = xml.Length - 1;
-			}
+			index = GetCorrectedIndex(xml.Length, index);
 		
 			// Move back one character if the last character is an '='
 			if (xml[index] == '=') {
@@ -202,9 +200,7 @@ namespace ICSharpCode.XmlEditor
 				return String.Empty;
 			}
 			
-			if (index >= xml.Length) {
-				index = xml.Length - 1;
-			}
+			index = GetCorrectedIndex(xml.Length, index);
 			
 			string name = String.Empty;
 			
@@ -299,6 +295,58 @@ namespace ICSharpCode.XmlEditor
 			
 			return false;
 		}
+		
+		/// <summary>
+		/// Determines whether the specified index is inside an attribute value.
+		/// </summary>
+		public static bool IsInsideAttributeValue(string xml, int index)
+		{
+			if (xml.Length == 0) {
+				return false;
+			}
+			
+			index = GetCorrectedIndex(xml.Length, index);
+						
+			int elementStartIndex = GetActiveElementStartIndex(xml, index);
+			if (elementStartIndex == - 1) {
+				return false;
+			}
+			
+			// Count the number of double quotes and single quotes that exist
+			// before the first equals sign encountered going backwards to
+			// the start of the active element.
+			bool foundEqualsSign = false;
+			int doubleQuotesCount = 0;
+			int singleQuotesCount = 0;
+			char lastQuoteChar = ' ';
+			for (int i = index; i > elementStartIndex; --i) {
+				char ch = xml[i];
+				if (ch == '=') {
+					foundEqualsSign = true;
+					break;
+				} else if (ch == '\"') {
+					lastQuoteChar = ch;
+					++doubleQuotesCount;
+				} else if (ch == '\'') {
+					lastQuoteChar = ch;
+					++singleQuotesCount;
+				}
+			}
+			
+			bool isInside = false;
+			
+			if (foundEqualsSign) {
+				// Odd number of quotes?
+				if ((lastQuoteChar == '\"') && ((doubleQuotesCount % 2) > 0)) {
+					isInside = true;
+				} else if ((lastQuoteChar == '\'') && ((singleQuotesCount %2) > 0)) {
+					isInside = true;
+				}
+			}
+			
+			return isInside;
+		}
+		
 		/// <summary>
 		/// Gets the text of the xml element start tag that the index is 
 		/// currently inside.
@@ -444,5 +492,21 @@ namespace ICSharpCode.XmlEditor
 			
 			return reversedString.ToString();
 		}
+		
+		/// <summary>
+		/// Ensures that the index is on the last character if it is
+		/// too large.
+		/// </summary>
+		/// <param name="length">The length of the string.</param>
+		/// <param name="index">The current index.</param>
+		/// <returns>The index unchanged if the index is smaller than the
+		/// length of the string; otherwise it returns length - 1.</returns>
+		static int GetCorrectedIndex(int length, int index)
+		{
+			if (index >= length) {
+				index = length - 1;
+			}
+			return index;
+		}
 	}
 }
diff --git a/src/AddIns/DisplayBindings/XmlEditor/Test/Parser/InsideAttributeValueTestFixture.cs b/src/AddIns/DisplayBindings/XmlEditor/Test/Parser/InsideAttributeValueTestFixture.cs
new file mode 100644
index 0000000000..0001e21245
--- /dev/null
+++ b/src/AddIns/DisplayBindings/XmlEditor/Test/Parser/InsideAttributeValueTestFixture.cs
@@ -0,0 +1,102 @@
+// <file>
+//     <copyright see="prj:///doc/copyright.txt"/>
+//     <license see="prj:///doc/license.txt"/>
+//     <owner name="Matthew Ward" email="mrward@users.sourceforge.net"/>
+//     <version>$Revision$</version>
+// </file>
+
+using ICSharpCode.XmlEditor;
+using NUnit.Framework;
+using System;
+using System.Xml;
+
+namespace XmlEditor.Tests.Parser
+{
+	[TestFixture]
+	public class InsideAttributeValueTestFixture
+	{
+		[Test]
+		public void InvalidString()
+		{
+			Assert.IsFalse(XmlParser.IsInsideAttributeValue(String.Empty, 10));
+		}
+		
+		[Test]
+		public void DoubleQuotesTest1()
+		{
+			string xml = "<foo a=\"";
+			Assert.IsTrue(XmlParser.IsInsideAttributeValue(xml, xml.Length));
+		}
+		
+		[Test]
+		public void DoubleQuotesTest2()
+		{
+			string xml = "<foo a=\"\" ";
+			Assert.IsFalse(XmlParser.IsInsideAttributeValue(xml, xml.Length));
+		}
+		
+		[Test]
+		public void DoubleQuotesTest3()
+		{
+			string xml = "<foo a=\"\"";
+			Assert.IsFalse(XmlParser.IsInsideAttributeValue(xml, xml.Length));
+		}
+		
+		[Test]
+		public void DoubleQuotesTest4()
+		{
+			string xml = "<foo a=\" ";
+			Assert.IsTrue(XmlParser.IsInsideAttributeValue(xml, xml.Length));
+		}
+
+		[Test]
+		public void NoXmlElementStart()
+		{
+			string xml = "foo a=\"";
+			Assert.IsFalse(XmlParser.IsInsideAttributeValue(xml, xml.Length));
+		}
+		
+		[Test]
+		public void EqualsSignTest()
+		{
+			string xml = "<foo a=";
+			Assert.IsFalse(XmlParser.IsInsideAttributeValue(xml, xml.Length));
+		}
+		
+		[Test]
+		public void SingleQuoteTest1()
+		{
+			string xml = "<foo a='";
+			Assert.IsTrue(XmlParser.IsInsideAttributeValue(xml, xml.Length));
+		}
+		
+		[Test]
+		public void MixedQuotesTest1()
+		{
+			string xml = "<foo a='\"";
+			Assert.IsTrue(XmlParser.IsInsideAttributeValue(xml, xml.Length));
+		}
+		
+		[Test]
+		public void MixedQuotesTest2()
+		{
+			string xml = "<foo a=\"'";
+			Assert.IsTrue(XmlParser.IsInsideAttributeValue(xml, xml.Length));
+		}
+		
+		[Test]
+		public void MixedQuotesTest3()
+		{
+			string xml = "<foo a=\"''";
+			Assert.IsTrue(XmlParser.IsInsideAttributeValue(xml, xml.Length));
+		}
+
+		[Test]
+		public void MixedQuotesTest4()
+		{
+			string xml = "<foo a=\"''\"";
+			Assert.IsFalse(XmlParser.IsInsideAttributeValue(xml, xml.Length));
+		}
+		
+	}
+}
diff --git a/src/AddIns/DisplayBindings/XmlEditor/Test/XmlEditor.Tests.csproj b/src/AddIns/DisplayBindings/XmlEditor/Test/XmlEditor.Tests.csproj
index ef15e95782..a6b26dcc52 100644
--- a/src/AddIns/DisplayBindings/XmlEditor/Test/XmlEditor.Tests.csproj
+++ b/src/AddIns/DisplayBindings/XmlEditor/Test/XmlEditor.Tests.csproj
@@ -91,6 +91,7 @@
     <Compile Include="Utils\SchemaIncludeTestFixtureHelper.cs" />
     <Compile Include="Schema\MissingSchemaElementTestFixture.cs" />
     <Compile Include="Schema\AllElementTestFixture.cs" />
+    <Compile Include="Parser\InsideAttributeValueTestFixture.cs" />
   </ItemGroup>
   <ItemGroup>
     <Folder Include="Schema\" />