Description:
------------
My build log for PHP 5.3 shows this in json.c:
 
gcc -Iext/json/ -I/home/cjones/phpsrc/php53/ext/json/ -DPHP_ATOM_INC -I/home/cjones/phpsrc/php53/include -I/home/cjones/phpsrc/php53/main -I/home/cjones/phpsrc/php53 -I/home/cjones/phpsrc/php53/ext/ereg/regex -I/usr/include/libxml2 -I/home/cjones/phpsrc/php53/ext/date/lib -I/home/cjones/instantclient_10_2/sdk/include -I/home/cjones/phpsrc/php53/TSRM -I/home/cjones/phpsrc/php53/Zend -I/usr/include -g -fvisibility=hidden -O0 -Wall -c /home/cjones/phpsrc/php53/ext/json/json.c -o ext/json/.libs/json.o
/home/cjones/phpsrc/php53/ext/json/json.c: In function 'json_encode_r':
/home/cjones/phpsrc/php53/ext/json/json.c:426: warning: unknown conversion type character 'k' in format
/home/cjones/phpsrc/php53/ext/json/json.c:426: warning: too many arguments for format

The same warning occurs on Ubuntu 7.10 and RHEL 4.  It also occurs with PHP 5.2.

My config.nice contains:

'./configure' \
'--prefix=/home/cjones/php53_10' \
'--with-apxs2=/home/cjones/apache/bin/apxs' \
'--enable-debug' \
'--with-gd' \
'--with-zlib' \
'--with-oci8=instantclient,/home/cjones/instantclient_10_2' \
'--enable-sigchild' \
"$@"