I was doing some tests, and noticed that mIRC wouldn't let go of one test DLL, even after /dll -u. $dll(0) returns 0, but the file stays locked.
I've never encountered it before with anything else, so it probably has something to do with DllExport
and VB.NET combination. I'd still assume this is not intended behaviour.
The only function the DLL has is HelloWorld, which returns "HelloWorld".