Using:
  mhash-0.8.1
  libmcrypt-2.4.2 (--disable-posix-threads)
  mcrypt-2.5.3

PHP ./configure script:

./configure \
        --with-apxs=/usr/local/apache/bin/apxs \
        --with-gd \
        --with-imap \
        --with-mysql \
        --with-zlib \
        --with-mcrypt \
        --with-mhash \
        --enable-track-vars

Results of 'make' in PHP directory.  (It compiles find without --mcrypt).

gcc -g -O2 -DLINUX=2 -DMOD_SSL=206102 -DUSE_HSREGEX -DEAPI -DUSE_EXPAT -I../lib/expat-lite -fpic -DSHARED_CORE -O2 -D
SHARED_MODULE  -I. -I.   -I/usr/local/apache/include                  -I/usr/include/mysql -I/usr/local/include    -c
 functions/mcrypt.c -o functions/mcrypt.o
functions/mcrypt.c:120: warning: `MCRYPT_FAILED' redefined
functions/mcrypt.mod.h:28: warning: this is the location of the previous definition
functions/mcrypt.c: In function `php_minit_mcrypt':
functions/mcrypt.c:139: `MCRYPT_BLOWFISH_448' undeclared (first use in this function)
functions/mcrypt.c:139: (Each undeclared identifier is reported only once
functions/mcrypt.c:139: for each function it appears in.)
functions/mcrypt.c:140: warning: passing arg 3 of `php3_register_long_constant' makes integer from pointer without a
cast
functions/mcrypt.c:141: warning: passing arg 3 of `php3_register_long_constant' makes integer from pointer without a
cast
functions/mcrypt.c:142: warning: passing arg 3 of `php3_register_long_constant' makes integer from pointer without a
cast
functions/mcrypt.c:143: warning: passing arg 3 of `php3_register_long_constant' makes integer from pointer without a
cast
functions/mcrypt.c:144: `MCRYPT_SAFER_64' undeclared (first use in this function)
functions/mcrypt.c:145: `MCRYPT_SAFER_128' undeclared (first use in this function)
functions/mcrypt.c:146: warning: passing arg 3 of `php3_register_long_constant' makes integer from pointer without a
cast
functions/mcrypt.c:147: warning: passing arg 3 of `php3_register_long_constant' makes integer from pointer without a
cast
functions/mcrypt.c:148: `MCRYPT_RC2_1024' undeclared (first use in this function)
functions/mcrypt.c:149: `MCRYPT_TWOFISH_128' undeclared (first use in this function)
functions/mcrypt.c:150: `MCRYPT_TWOFISH_192' undeclared (first use in this function)
functions/mcrypt.c:151: `MCRYPT_TWOFISH_256' undeclared (first use in this function)
functions/mcrypt.c:152: `MCRYPT_BLOWFISH_128' undeclared (first use in this function)
functions/mcrypt.c:153: `MCRYPT_BLOWFISH_192' undeclared (first use in this function)
functions/mcrypt.c:154: `MCRYPT_BLOWFISH_256' undeclared (first use in this function)
functions/mcrypt.c:155: warning: passing arg 3 of `php3_register_long_constant' makes integer from pointer without a
cast
functions/mcrypt.c:156: warning: passing arg 3 of `php3_register_long_constant' makes integer from pointer without a
cast
functions/mcrypt.c:157: warning: passing arg 3 of `php3_register_long_constant' makes integer from pointer without a
cast
functions/mcrypt.c:158: `MCRYPT_SERPENT_128' undeclared (first use in this function)
functions/mcrypt.c:159: `MCRYPT_SERPENT_192' undeclared (first use in this function)
functions/mcrypt.c:160: `MCRYPT_SERPENT_256' undeclared (first use in this function)
functions/mcrypt.c:161: warning: passing arg 3 of `php3_register_long_constant' makes integer from pointer without a
cast
functions/mcrypt.c:162: warning: passing arg 3 of `php3_register_long_constant' makes integer from pointer without a
cast
functions/mcrypt.c:163: warning: passing arg 3 of `php3_register_long_constant' makes integer from pointer without a
cast
functions/mcrypt.c:164: `MCRYPT_RC2_256' undeclared (first use in this function)
functions/mcrypt.c:165: `MCRYPT_RC2_128' undeclared (first use in this function)
functions/mcrypt.c:166: `MCRYPT_RC6_256' undeclared (first use in this function)
functions/mcrypt.c:167: `MCRYPT_IDEA' undeclared (first use in this function)
functions/mcrypt.c:168: `MCRYPT_RC6_128' undeclared (first use in this function)
functions/mcrypt.c:169: `MCRYPT_RC6_192' undeclared (first use in this function)
functions/mcrypt.c:170: `MCRYPT_RC4' undeclared (first use in this function)
functions/mcrypt.c: In function `php3_mcrypt_get_cipher_name':
functions/mcrypt.c:243: warning: assignment makes pointer from integer without a cast
make: *** [functions/mcrypt.o] Error 1