Linux: question marks in file status; cannot stat file

Linux 2.6.18-164.11.1.el5.centos.plus
filesystem in question: reiserfs

Hi,

I'm having trouble deleting a file:

[root@flat: all_subjs_wcbf]# ls -lah
total 0
drwxrwxrwx 2 szhu cfn 88 Sep  1  2011 ./
drwxrwxrwx 3 szhu cfn 80 Jun  8  2011 ../
?--------- ? ?    ?    ?            ? sub13_AVG_5_cbf.m

[root@flat: all_subjs_wcbf]# rm sub13_AVG_5_cbf.m 
rm: cannot lstat `sub13_AVG_5_cbf.m': Permission denied

Looking at other posts on serverfault and stackoverflow for suggestions:

• the dir and containing dir's all have executable permission set, for all users. I've tried setting all containing dirs to 777 again at the same time just in case, but still cannot lstat.
• there are no associated IO errors reported.

I've tried "rm -rf" and "rm -i" just in case. No luck.

I'll eventually pull the disk offline and check it, but want to put that off because it's heavily used. So if this is not a disk error and can be fixed now, it'd be a great help! Thanks.

-Michael