rotten Bleeder Valve on ABS Compressor/Proporsioning valve

One of the bleeder valves on the ABS Hydraulic control unit/motor pack appears to be rotted from the inside, when i press the brake, fluid flows right out. This is located on the left side of the car under the battery. I tried to tighten and losen it and even with some heat and penetrating oil, it would not budge. Aside from taking the whole assembly out of the car which appears to be quite the task is there any way i can seal this bleeder valve? The white stuff around it is from an extinguisher as the tinfoil i used to keep the washer fluid tank from melting went up in flames...

http://home.comcast.net/~nqc2k/pic.jpg

gave up....limped her to my local mechanic, and will let him play with it for awhile.

Where in Ma are you from? Im from Holyoke!