I tried to get around of bug 4747 http://bugs.php.net/bugs.php?id=4747 and recompiled PHP without DSO. 
I use Oracle 7.3.2 on Solaris x86. PHP3 works/compiles just fine.
Configure line:
./configure  \
--with-jpeg-dir=/usr/local \
--with-gd --with-oracle \
--with-mysql \
--with-config-file-path=/h/home/kir/SOFT/conf \
--with-apache=../apache_1.3.12 \
--disable-debug \
--enable-magic-quotes=yes \
--enable-memory-limit=yes \
--enable-url-fopen-wrapper=no \
--enable-sysvsem=yes \
--enable-sysvshm=yes  \
--enable-track-vars=yes \
--with-system-regex \
--enable-safe-mode \
--with-gdbm \
--enable-ftp 

make in Apache tree gives an error:
gcc  -DSOLARIS2=270 -I/h/home/kir/SRC/php4
 -I/h/home/kir/SRC/php4/main -I/h/home/kir/SRC/php4/main -I/h/home/kir/SRC/php4/Zend -I/h/home/kir/SRC/php4/Zend -I/h/home/kir/SRC/php4 -DUSE_EXPAT -I./lib/expat-lite `./apaci`    \
      -o httpd buildmark.o modules.o modules/standard/libstandard.a modules/php4/libphp4.a modules/extra/libextra.a main/libmain.a ./os/unix/libos.a ap/libap.a
 lib/expat-lite/libexpat.a  -R/usr/ucblib -R/usr/local/lib -R/u/oracle7/lib  -L/usr/ucblib
 -L/usr/local/lib -L/u/oracle7/lib -Lmodules/php4 -L../modules/php4 -L
../../modules/php4 -lmodphp4  -lgdbm -lpam  -ldl -lncr -lsqlnet -lclient -lcommon 
-lgeneric -lepc -lc3v6 -lnlsrtl3 -lcore3 -lposix4 -laio -lm -lttf -ljpeg -lz -lpng
 -lgd -lgdbm -lresolv -lresolv -lm -ldl -lcrypt -lnsl -lsocket  -lsocket -L/usr/local/lib
 -ljpeg  -lsocket -lnsl -ldl
Undefined                       first referenced
 symbol                             in file
lxhninfo                            /u/oracle7/lib/libcore3.a(ldxdow.o)
lxmalnx                             /u/oracle7/lib/libcore3.a(ldxpv.o)
lxnchar                             /u/oracle7/lib/libcore3.a(ldxpv.o)
lxmblax                             /u/oracle7/lib/libcore3.a(ldxpv.o)
lxm2wlx                             /u/oracle7/lib/libcore3.a(ldxsnf.o)
nscontrol                           /u/oracle7/lib/libclient.a(upicdc.o)
nszssk                              /u/oracle7/lib/libclient.a(upilog.o)
lxmcpnx                             /u/oracle7/lib/libcore3.a(ldxsnf.o)
lxmuppx                             /u/oracle7/lib/libcore3.a(ldxsnf.o)
lxicmi                              /u/oracle7/lib/libcore3.a(ldxpv.o)
lxeifnd                             /u/oracle7/lib/libcore3.a(ldxpv.o)
lxrnorm                             /u/oracle7/lib/libcore3.a(lmxe.o)
osncon                              /u/oracle7/lib/libclient.a(upiprv.o)
lxmlowx                             /u/oracle7/lib/libcore3.a(ldxsnf.o)
lxmcpl                              /u/oracle7/lib/libcore3.a(ldxmfn.o)
lxt24s                              /u/oracle7/lib/libcore3.a(ldxpv.o)
lxhmnorm                            /u/oracle7/lib/libcore3.a(lmxe.o)
lxeu2g                              /u/oracle7/lib/libcore3.a(ldxstd.o)
lxtrmm                              /u/oracle7/lib/libcore3.a(ldxpv.o)
nsexport                            /u/oracle7/lib/libclient.a(upicdc.o)
lxlfndl                             /u/oracle7/lib/libcore3.a(ldxpv.o)
lxhasc                              /u/oracle7/lib/libcore3.a(lnxscn.o)
ld: fatal: Symbol referencing errors. No output written to httpd
collect2: ld returned 1 exit status
make[2]: *** [target_static] Error 1

I suggest there is a problem in the order of Oracle libraries in link command,
because in PHP3 link coomand most libraries like -lcommon appears two or
 even three times.
Here each Oracle library is presented only once.