Anyone around to peek on the logs to try and point me to a good direction?

It seems the errors occurred when the concurrency happens between requests to the mono process:

(mono log)
[2010-03-15 11:27:10Z] Debug Accepting an incoming connection.
[2010-03-15 11:27:10Z] Debug Accepting an incoming connection.
[2010-03-15 11:27:10Z] Debug Record received. (Type: BeginRequest, ID: 1, Length: 8)
[2010-03-15 11:27:10Z] Debug Accepting an incoming connection.
[2010-03-15 11:27:10Z] Debug Record received. (Type: Params, ID: 1, Length: 529)
[2010-03-15 11:27:10Z] Debug Record received. (Type: BeginRequest, ID: 1, Length: 8)
[2010-03-15 11:27:10Z] Debug Record received. (Type: Params, ID: 1, Length: 0)
[2010-03-15 11:27:10Z] Debug Record sent. (Type: EndRequest, ID: 1, Length: 8)

He signals the End Request to other requests it seems. I continue to pursue if this is a nginx problem or a mono problem :(

Regards,
Ribeiro