SunPro for old Solaris releases

Hi,

does anyone know which SunPro releases will run on Solaris 2.1, 2.2
or 2.3? (really, no joke here.)
I found references that for 2.1 and 2.2 you need a SunPro in the
2.X range while 2.3 will work with a 3.X SunPro, but I couldn't
find a compatibility chart.
The SunPro would be needed for building a first gcc release only.
Hints where to find gcc binaries for the older systems would be
great too. The oldest gcc I found is for 2.3.

thanks,
Dennis

--
Don't suffer from insanity...
Enjoy every minute of it.
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