I can't give you full answer but this reminded me that back in 2007 I'd had an issue with Oracle requiring "Motif" and the Fedora system I was installing at the time didn't have that in repositories. Instead it had "lesstif" and on installing that it provided what was needed for Oracle (EBIZ R12) to run.
On checking I do see mention of lesstif for Solaris (unfortunately it only mentions 2.6) at the site below. It does however, mention a couple of patches done to make it work on Solaris that might give you some ideas.
I haven't done anything with lesstif on Solaris but on Fedora it simply worked in place of what Oracle was expecting from Motif.