I too am having a very similar issue. The only real difference is that we use actual Dictionaries instead of IDictionary. I believe the issue stems from having a custom or complex type as either the key or value in your dictionary. I have tested it sending a string for the key and an int for the value and it works fine.
I have also used fiddler to examine the difference in the SOAP between the XML that mono sends and the xml that .NET or Silverlight sends. What I have found is that .NET and Silverlight appends what appears to be a seemingly random set of characters onto the end of the type name. But in truth it must not be random because through different projects and compiles the string remains consistent. I have also noticed that it changes depending on what namespace your custom class is in. So it must be some form of digest of a namespace. Without this, the WCF server is unable to deserialize the dictionary properly. Below is an example of the dictionary in XML created by mono and then the XML created by .NET. This is in a namespace called Joe and is a dictionary keyed by string with a value of type SimpleTest. Mono: <d4p1:NewDict xmlns:d5p1="http://schemas.microsoft.com/2003/10/Serialization/Arrays"> <d5p1:KeyValueOfstringSimpleTest> <d5p1:Key>TestKey1</d5p1:Key> <d5p1:Value> <int1 xmlns="http://schemas.datacontract.org/2004/07/Origin.BLL.Joe">1</int1> <string1 xmlns="http://schemas.datacontract.org/2004/07/Origin.BLL.Joe">Test1</string1 </d5p1:Value> </d5p1:KeyValueOfstringSimpleTest> </d4p1:NewDict> .NET <d4p1:NewDict xmlns:d5p1="http://schemas.microsoft.com/2003/10/Serialization/Arrays"> <d5p1:KeyValueOfstringSimpleTest3HyOSdeZ> <d5p1:Key>TestKey1</d5p1:Key> <d5p1:Value xmlns:d7p1="http://schemas.datacontract.org/2004/07/Origin.BLL.Joe"> <d7p1:int1>1</d7p1:int1> <d7p1:string1>Test1</d7p1:string1> </d5p1:Value> </d5p1:KeyValueOfstringSimpleTest3HyOSdeZ> </d4p1:NewDict> Notice how .NET appends "3HyOSdeZ" on the end of SimpleTest. Where you able to come up with a solution to your issue? -- View this message in context: http://mono-for-android.1047100.n5.nabble.com/Can-not-send-IDictionary-to-WCF-tp4908854p5081325.html Sent from the Mono for Android mailing list archive at Nabble.com. _______________________________________________ Monodroid mailing list Monodroid@lists.ximian.com UNSUBSCRIBE INFORMATION: http://lists.ximian.com/mailman/listinfo/monodroid