Hello all,

I have installed the latest libmcrypt 2.5.7 on /usr/local/libmcrypt

in the PHP 4.3.1 source file directory :
# ./configure --with-mcrypt=/usr/local/libmcrypt
return no errors

# make
failed with errors

It's because configure script doesn't recognize correctly
the library version (I think it detects 2.2)

in ext/mcryt/mcrypt.c I had to manually add:

#undef HAVE_LIBMCRYPT22
#define HAVE_LIBMCRYPT24

to force libmcrypt 2.4 compatibility

then it compiles OK

here is a part of the config.log for mcrypt :
------------------------------------------------------------
configure:41314: checking for mcrypt support
configure:41374: checking for mcrypt_module_open in -lmcrypt
configure:41393: gcc -o conftest -g -O2  
    -L/usr/local/libmcrypt/lib -lltdl
    conftest.c -lmcrypt  -lcrypt -lresolv -lm -ldl -lnsl  -lcrypt 1>&5
/usr/bin/ld: cannot find -lltdl
collect2: ld returned 1 exit status
configure: failed program was:
#line 41382 "configure"
#include "confdefs.h"
/* Override any gcc2 internal prototype to avoid an error.  */
/* We use char because int might match the return type of a gcc2
    builtin and then its argument prototype would still apply.  */
char mcrypt_module_open();

int main() {
mcrypt_module_open()
; return 0; }
configure:41510: checking for init_mcrypt in -lmcrypt
configure:41529: gcc -o conftest -g -O2  
      -L/usr/local/libmcrypt/lib
      conftest.c -lmcrypt  -lcrypt -lresolv -lm -ldl -lnsl  -lcrypt 1>&5
------------------------------------------------------------