problem with emerge php

[zazxxx]

i got problem when emerge php.

i already config USE with these

"sse sse2 apache2 berkdb bzip2 cli cgi curl fpm ftp gd gd-externel gdbm gpm hardened modules mysql mysqli multilib ncurses nls readline perl php python simplexml smp snmp setup threads vhosts xml xmlrpc unicode ssl zlib truetype ldap sockects pcre imap ipv6 -netlink -tk -wininst -build -xml -xmlreader -xmlwriter"

but every time i try to emerge php, it report with this note

The following REQUIRED_USE flag constraints are unsatisfied:
simplexml? ( xml )

i really dont know what's happen here!

[SLBMEH]

why do you have xml and -xml?

please post your emerge --info

That's saying that you are using the simplexml use flag and php requires xml if you have simplexml.