"Unable to read beyond the end of the stream" Error

"Unable to read beyond the end of the stream" Error

I'm trying to upgrade from 1.5.4b to 1.5.7; One of the test assemblies always fails to (n)covered.
I'm Using it with NUnit 2.2.6 and a simple very basic command with //w & //x switches.

here's a snippet of the output:
.................F..........................................................................................................................
.................F.F....................................
Tests run: 193, Failures: 3, Not run: 0, Time: 17.427 seconds

Failures:
1) TestIBMApplicationAlgorithms.TestAuthenticateMGCParticipantHandler.TestAuthenticateMcuParticipant_Normal_nonSIP : System.NullReferenceException : Object reference not set to an instance of an object.
   at ...
2) TestIBMApplicationAlgorithms.TestStartConferenceAlgorithm.TestStartConferenceAlgorithmVerification : System.InvalidCastException : Specified cast is not valid.
Server stack trace:
   [...]
3) TestIBMApplicationAlgorithms.TestStartConferenceAlgorithm.TestStartConferenceAlgorithmVerificationWithCommandFailed : System.InvalidCastException : Specified cast is not valid.
Server stack trace:
   [...]
Unable to read beyond the end of the stream.

Did some had the same problem with 1.5.7? An yidea what might have cause it?

`Moshe

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