problem running apt-get -b

[Faheem Mitha <faheem@email.unc.edu>]

Dear people,

I recently changed my user id (faheem) from 1000 to 500. I tried to run
apt-get build pgp4pine just now as root in my home directory (the first
time after changing the id, I think) and I discovered that something has
got bollixeded up. I get

/usr/bin/dpkg-buildpackage: debian/rules: Permission denied
Build command 'cd pgp4pine-1.75-6 && dpkg-buildpackage -b -uc' failed.
E: Child process failed

and more strangely, a list of the relevant files gives

drwxr-xr-x    4 1000     faheem       1024 Jul 11 19:37 pgp4pine-1.75-6
-rw-r--r--    1 root     root        11039 May 14 11:16
pgp4pine_1.75-6-1.diff.gz
-rw-r--r--    1 root     root          599 May 14 11:16
pgp4pine_1.75-6-1.dsc
-rw-r--r--    1 root     root        85239 May 14 11:16 
pgp4pine_1.75-6.orig.tar.gz

Note the user 1000. Since I changed the id, there is no longer a user
1000, so there is clearly something wrong. Apparently at least one of the
package tools thinks that my id is still 1000. I tried building (as root)
in /tmp (ie not my home directory) and it works OK. So the problem is to
do with my user status. Presumably there is a place somewhere that has me
recorded as having user id 1000, and I need to change it.

Can anyone tell me where that might be and what to do?

Thanks.

                        Sincerely, Faheem Mitha.