Ok, here's the output from sbevents.txt in my case. As you wrote the value for the fonts directory isn't retrieved:

|01/31/2012|12:41:02.993|Set Variable {FONTSDIR} to
|01/31/2012|12:41:02.993|Set Variable %FONTSDIR% to

...so, what does this mean? ...i guess i can manually test for server OS and eventually set the %FONTSDIR% by myself?