png problem compiling imlib

[Todd Graham Lewis <tlewis mindspring net>]

save.c: In function `Imlib_save_image':
save.c:353: `PNG_INTERLACE_NONE' undeclared (first use this function)
save.c:353: (Each undeclared identifier is reported only once
save.c:353: for each function it appears in.)
save.c:354: `PNG_COMPRESSION_TYPE_BASE' undeclared (first use this function)
save.c:354: `PNG_FILTER_TYPE_BASE' undeclared (first use this function)
make[2]: *** [save.lo] Error 1
make[2]: Leaving directory `/home/tlewis/gnome/cvs/gnome/imlib/Imlib'

Do I need a new verison of a png development thingie or something?

-- 
Todd Graham Lewis       tlewis@mindspring.net      (800) 719-4664, x2804

"It's still ludicrous that nobody's ever made a run at us by making UNIX
 a popular platform on PCs.  It's almost too late now."  -- Steve Balmer
"It is too late."   -- Bill Gates             _Newsweek_, 6/23/97, p. 82