Installation Issues - SCO Openserver 5

I have an old sco openserver 5 box that still gets a ton of work here at
work.
Trying to get ruby installed on it.
Configure runs with out a hitch but during make i get the following
error…

…/…/.ext/i686-sco3.2v5.0.6/bigdecimal.so: fatal error: Symbol
referencing
errors. No output written to …/…/.ext/i686-sco3.2v5.0.6/bigdecimal.so
make[1]: *** […/…/.ext/i686-sco3.2v5.0.6/bigdecimal.so] Error 1
make[1]: Leaving directory `/pm6/reports/ruby-1.8.4/ext/bigdecimal’
make: *** [all] Error 1

*Not even sure this is the write place to post this so if not please
direct
me to where I should be asking.

Paul