I get this error after debugging in Eclipse. The debug is successful though.
ERROR: JDWP Unable to get JNI 1.2 environment, jvm->GetEnv() return code = -2
JDWP exit error AGENT_ERROR_NO_JNI_ENV(183): [../../../src/share/back/util.c:820]
Looks like http://bugs.sun.com/view_bug.do?bug_id=6476706 which has low priority and is still not fixed. Definitely a Mustang bug but no clear explanation (seems to occur pretty randomly according to the bug reporters on top of that).