error upgrading to firefox 7.0.1_2,1

[Barbara]

I'm receiving an error even upgrading to the "rollbacked" version.
This time during the tests:

localhost.my.domain - - [21/Oct/2011 08:52:25] "GET /js-input/string-validate-
input.html HTTP/1.1" 200 -
TEST-UNEXPECTED-FAIL | automation.py | Exited with code -4 during test run
INFO | automation.py | Application ran for: 0:01:45.274818
INFO | automation.py | Reading PID log: /tmp/tmpEVEBFzpidlog
gmake: *** [profiledbuild] Error 252
*** Error code 1

Stop in /usr/ports/www/firefox.
*** Error code 1

Stop in /usr/ports/www/firefox.
** Command failed [exit code 1]: /usr/bin/script -qa /tmp/portupgrade20111021-
66241-w5nsb3-0 env UPGRADE_TOOL=portupgrade UPGRADE_PORT=firefox-7.0.1,1 
UPGRADE_PORT_VER=7.0.1,1 make WITH_PGO=1 WITH_OPTIMIZED_CFLAGS=1 
DEPENDS_TARGET=package
** Fix the problem and try again.
** Listing the failed packages (-:ignored / *:skipped / !:failed)
        ! www/firefox (firefox-7.0.1,1) (unknown build error)

Barbara