I don't know if this is helpful to you, but I'm planning on releasing an I/O filter DLL somewhere in the next week... This DLL allows scripts to examine and block all incoming and outgoing message lines, using a rule-based system; it hooks into mIRC's internal line send and line receive functions, which basically means SSL support at the cost of high dependence on the mIRC binary (6.14/6.15 only at this moment).
I will not release the source code (at least for a while), but if you want, I could add a few API calls that allow other DLLs to make use of it... Let me know if you're interested.
