If you use the SunSoft Print Client software instead of the /etc/lp
goo (which in general I'd highly recommend) then it comes with a
script that will convert an /etc/printcap file into a
/etc/printers.conf file, which is what the SSPC stuff needs.
You can download the SSPC software from
http://www.sun.com/smcc/solaris-migration/SSPC/index.html. Note the
recent patch for SSPC, 103182, unfortunately is currently only
available with a support contract, and does not yet appear to be
incorporated into the downloadable tar archive.