Regular Expression help

<?php echo 'Is String: [' . ( is_string( 'a1b2c3' ) && preg_match( '/[A-Za-z]+/', 'a1b2c3' )) . ']<br>'; echo 'Is Numeric: [' . ( is_numeric( 'a1b2c3' ) && preg_match( '/[0-9]+/', 'a1b2c3' )) . ']<br>'; echo 'Is String: [' . ( is_string( 'abcdef' ) && preg_match( '/[A-Za-z]+/', 'abcdef' )) . ']<br>'; echo 'Is Numeric: [' . ( is_numeric( '123456' ) && preg_match( '/[0-9]+/', '123456' )) . ']<br>'; ?> Why is the first "Is String" check returning true/showing 1? preg_match should fail because 'a1b2c3' contains numbers and, as such, doesn't match the pattern... What am I doing wrong? thnx, Chris