Created Unassigned: TestGC unit test fails if all the test suite is run [39]

Same behavior run on Windows 7, 64 bits, NUnutGUI or from VS 2012.
the test passes if run along the tests in the same class, but may fail subsequently once it has failed once.

RDotNet.ParseException was unhandled by user code
HResult=-2146232832
Message=Error in the application.
Source=RDotNet
StackTrace:
at RDotNet.REngine.Parse(String statement, StringBuilder incompleteStatement) in f:\codeplex\rdotnet\R.NET\REngine.cs:line 464
at RDotNet.REngine.<Defer>d__0.MoveNext() in f:\codeplex\rdotnet\R.NET\REngine.cs:line 372
at System.Linq.Enumerable.LastOrDefault[TSource](IEnumerable`1 source)
at RDotNet.REngine.Evaluate(String statement) in f:\codeplex\rdotnet\R.NET\REngine.cs:line 331
at RDotNet.Tests.REngineTest.TestGC() in f:\codeplex\rdotnet\RDotNet.Tests\REngineTest.cs:line 71
InnerException: