after successful

 ./configure  --with-mysql \
              --with-apache=../apache_1.3.6 \
              --with-gd=/usr/local \
              --with-zlib \
              --with-tiff-dir=/usr/lib \
              --with-pdflib=/usr/local \
              --with-ttf \
              --enable-track-vars \
              --enable-magic-quotes

make produce the following error-message:

gcc -g -O2 -O2   -I. -I.   -I../apache_1.3.6/src/include -I../apache_1.3.6/src/os/unix            -I/usr/local/include      -I/usr/local/include -I/usr/include -I/usr/include/mysql    -c functions/pdf.c -o functions/pdf.o
functions/pdf.c: In function `php3_pdf_open_memory_image':
functions/pdf.c:2134: `gdImagePtr' undeclared (first use in this function)
functions/pdf.c:2134: (Each undeclared identifier is reported only once
functions/pdf.c:2134: for each function it appears in.)
functions/pdf.c:2134: parse error before `im'
functions/pdf.c:2153: `im' undeclared (first use in this function)
make: *** [functions/pdf.o] Error 1

Whats going on??