Epson iscan library oddity

I've successfully compiled Epson's iscan scanner driver for my 1650 Perfection ( http://www.epkowa.co.jp/english/linux_e/dl_scan.html) but in the lib/sane directory all the files are missing "so" from their names, though the precompiled rpm has them. Does anybody know what to do to the Makefile to get them named correctly? Geoff