installation of xmgrace on Slackware 13.1

I am installing grace-5.1.9 with t1lib-5.1.2 installed.

Problems:

t1fonts.c:(.text+0x336b): undefined reference to `T1_Get_no_fonts'
fontwin.c:(.text+0x141): undefined reference to `CheckForFontID'

Solutions:

change T1_Get_no_fonts in src/t1fonts.c to T1_GetNoFonts
change CheckForFontID in src/fontwin.c to T1_CheckForFontID