Build-Problem with pgc.c on OSX 10.4

Hi

When I try to build CVS HEAD on OSX 10.4, compiling
src/interfaces/ecpg/preproc/preproc.c fails with:
In file included from preproc.y:6951:
pgc.l:3:20: error: config.h: No such file or directory
In file included from pgc.l:28,                 from preproc.y:6951:
preproc.h:996: error: conflicting types for 'base_yylloc'
y.tab.c:18673: error: previous declaration of 'base_yylloc' was here
In file included from preproc.y:6951:
pgc.l:43: error: 'MAX_PARSE_BUFFER' undeclared here (not in a function)

If I delete pgc.c, it is rebuilt automatically, and then
preproc.c compiles just fine.

I'm using gcc 4.0.1, flex 2.5.4 and bison 2.3

greetings, Florian Pflug