git-mergetool changes file rights?

Hello,

I've stumbled upon very weird problem: grek@linux-p3yg:~/asf/git/infrastructure/apache-git-mirrors/bin> git --version git version 1.6.1.3 grek@linux-p3yg:~/asf/git/infrastructure/apache-git-mirrors/bin> ls -l razem 40 -rwxr-xr-x 1 grek users 773 mar 7 16:47 create-repo.sh -rwxr-xr-x 1 grek users 3219 mar 7 16:50 email-update.sh -rwxr-xr-x 1 grek users 3219 mar 7 16:50 email-update.sh.orig -rwxr-xr-x 1 grek users 2086 mar 7 16:47 move-svn-project.sh -rwxr-xr-x 1 grek users 1464 mar 7 16:47 update-authors.sh -rwxr-xr-x 1 grek users 156 mar 6 16:16 update-daily.sh -rwxr-xr-x 1 grek users 371 mar 7 16:47 update-every-minute.sh -rwxr-xr-x 1 grek users 215 mar 7 16:47 update-gitweb.sh -rwxr-xr-x 1 grek users 1104 mar 7 16:47 update-repo.sh -rwxr-xr-x 1 grek users 188 mar 7 16:47 update.sh grek@linux-p3yg:~/asf/git/infrastructure/apache-git-mirrors/bin> git mergetool merge tool candidates: kdiff3 kdiff3 tkdiff xxdiff meld gvimdiff opendiff emerge vimdiff Merging the files: email-update.sh

Normal merge conflict for 'email-update.sh':
  {local}: modified
  {remote}: modified
Hit return to start merge resolution tool (kdiff3):
error: open("bin/email-update.sh"): Permission denied
error: unable to index file bin/email-update.sh
fatal: updating files failed
grek@linux-p3yg:~/asf/git/infrastructure/apache-git-mirrors/bin> ls -l
razem 40
-rwxr-xr-x 1 grek users  773 mar  7 16:47 create-repo.sh
---x------ 1 grek users 3219 mar  7 16:53 email-update.sh
-rwxr-xr-x 1 grek users 3219 mar  7 16:53 email-update.sh.orig
-rwxr-xr-x 1 grek users 2086 mar  7 16:47 move-svn-project.sh
-rwxr-xr-x 1 grek users 1464 mar  7 16:47 update-authors.sh
-rwxr-xr-x 1 grek users  156 mar  6 16:16 update-daily.sh
-rwxr-xr-x 1 grek users  371 mar  7 16:47 update-every-minute.sh
-rwxr-xr-x 1 grek users  215 mar  7 16:47 update-gitweb.sh
-rwxr-xr-x 1 grek users 1104 mar  7 16:47 update-repo.sh
-rwxr-xr-x 1 grek users  188 mar  7 16:47 update.sh

Notice rights for email-update.sh.

What's going on here?