mount fat/vfat (fat32)

I'v built a dual boot config using lilo on a 80G HDD:
first   W2Kprof about 10G
second  Debian on kernel 2.4.18 also about 10G
third   some swap about 256M
remind  two logical partitions about 30 - 30G each to use them commonly

Made two mount points
/mnt/dsk1 and /mnt/dsk2
owner is root, group is users and add myself (user) to group users

I'm mounting as
mount -o uid=0,gid=100,umask=0003,noexec,codepage=852 /dev/hda5 /mnt/dsk1

Now comes the confuse, copied a simple tar file to my partition appiers as 
executable!?
I'm tried umask=0013 (-x) - partition became unwriteable!
Any ideas?