Description:
------------
Looks like PHP_5_3 doesn't compile on my FreeBSD 6.2 system if the pcntl extension is enabled.

Reproduce code:
---------------
./configure --disable-cgi --enable-pcntl
make

Expected result:
----------------
No error :)

Actual result:
--------------
/usr/local/bin/bash /root/compile/php-5.3/libtool --silent --preserve-dup-deps --mode=compile cc  -Iext/pcntl/ -I/root/compile/php-5.3/ext/pcntl/ -DPHP_ATOM_INC -I/root/compile/php-5.3/include -I/root/compile/php-5.3/main -I/root/compile/php-5.3 -I/root/compile/php-5.3/ext/ereg/regex -I/usr/local/include/libxml2 -I/usr/local/include -I/root/compile/php-5.3/ext/date/lib -I/root/compile/php-5.3/ext/sqlite3/libsqlite -I/root/compile/php-5.3/TSRM -I/root/compile/php-5.3/Zend    -I/usr/local/include -g -O2  -c /root/compile/php-5.3/ext/pcntl/pcntl.c -o ext/pcntl/pcntl.lo
/root/compile/php-5.3/ext/pcntl/pcntl.c: In function `php_register_signal_constants':
/root/compile/php-5.3/ext/pcntl/pcntl.c:293: error: `CLD_EXITED' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:293: error: (Each undeclared identifier is reported only once
/root/compile/php-5.3/ext/pcntl/pcntl.c:293: error: for each function it appears in.)
/root/compile/php-5.3/ext/pcntl/pcntl.c:294: error: `CLD_KILLED' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:295: error: `CLD_DUMPED' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:296: error: `CLD_TRAPPED' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:297: error: `CLD_STOPPED' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:298: error: `CLD_CONTINUED' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:301: error: `TRAP_BRKPT' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:302: error: `TRAP_TRACE' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:305: error: `POLL_IN' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:306: error: `POLL_OUT' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:307: error: `POLL_MSG' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:308: error: `POLL_ERR' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:309: error: `POLL_PRI' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:310: error: `POLL_HUP' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:312: error: `ILL_ILLOPC' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:313: error: `ILL_ILLOPN' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:314: error: `ILL_ILLADR' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:315: error: `ILL_ILLTRP' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:316: error: `ILL_PRVOPC' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:317: error: `ILL_PRVREG' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:318: error: `ILL_COPROC' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:319: error: `ILL_BADSTK' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:330: error: `SEGV_MAPERR' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:331: error: `SEGV_ACCERR' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:333: error: `BUS_ADRALN' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:334: error: `BUS_ADRERR' undeclared (first use in this function)
/root/compile/php-5.3/ext/pcntl/pcntl.c:335: error: `BUS_OBJERR' undeclared (first use in this function)
*** Error code 1