title: Method not found: 'System.Threading.Monitor.Enter' with Nhibernate, Mono & SQLite
body: <p>I'm trying to port an existing NHibernate project from using MySQL to using SQLite and I'm running into an interesting error when I try and run the tests:</p>
  
  <pre><code>1) ProductRepository_Fixture : System.MissingMethodException : Method not found: 'System.Threading.Monitor.Enter'.
  </code></pre>
  
  <p>I've tried googling this error with no luck. I assume that I must be missing a reference of some kind - but I can't figure out what...</p>
  
  <p>This is all being done on Mono.</p>
  
  <p>Any ideas at all what I'm missing?</p>
  
  <p><strong>Update:</strong> Have since found a further error message that I hadn't spotted before:</p>
  
  <pre><code>.Missing method System.Type::op_Equality(Type,Type) in assembly /usr/lib/mono/2.0/mscorlib.dll, referenced in assembly /tmp/nunit20/ShadowCopyCache/4606_634431542912600100/Tests/assembly/shadow/fa3c43db/9b71732a_614d30f1_00000001/Mono.Data.Sqlite.dll
  Missing method System.Threading.Monitor::Enter(object,bool&amp;) in assembly /usr/lib/mono/2.0/mscorlib.dll, referenced in assembly /tmp/nunit20/ShadowCopyCache/4606_634431542912600100/Tests/assembly/shadow/fa3c43db/9b71732a_614d30f1_00000001/Mono.Data.Sqlite.dll
  F    Missing method System.Threading.Monitor::Enter(object,bool&amp;) in assembly /usr/lib/mono/2.0/mscorlib.dll, referenced in assembly /tmp/nunit20/ShadowCopyCache/4606_634431542912600100/Tests/assembly/shadow/fa3c43db/9b71732a_614d30f1_00000001/Mono.Data.Sqlite.dll
  Missing method System.Threading.Monitor::Enter(object,bool&amp;) in assembly /usr/lib/mono/2.0/mscorlib.dll, referenced in assembly /tmp/nunit20/ShadowCopyCache/4606_634431542912600100/Tests/assembly/shadow/fa3c43db/9b71732a_614d30f1_00000001/Mono.Data.Sqlite.dll
  .F.F.F.FMissing method System.Threading.Monitor::Enter(object,bool&amp;) in assembly /usr/lib/mono/2.0/mscorlib.dll, referenced in assembly /tmp/nunit20/ShadowCopyCache/4606_634431542912600100/Tests/assembly/shadow/fa3c43db/9b71732a_614d30f1_00000001/Mono.Data.Sqlite.dll
  </code></pre>