AFAIK I'm not using supermount, but I tried running supermount -i disable just in case and still get the same errors. Here is my /etc/fstab if it helps:
/dev/hda7 / ext2 noatime 1 1
none /dev/pts devpts mode=0620 0 0
none /dev/shm tmpfs defaults 0 0
/dev/hda1 /mnt/c vfat iocharset=iso8859-1,codepage=850 0 0
/dev/hdc /mnt/cdrom auto iocharset=iso8859-1,codepage=850,noauto,ro,nosuid,user,exec,nodev0 0
/dev/fd0 /mnt/floppy auto codepage=850,iocharset=iso8859-1,noauto,nosuid,sync,user,unhide,nodev,exec 0 0
none /proc proc defaults 0 0
/dev/hda6 swap swap defaults 0 0
/dev/sda1 /mnt/removable auto user,exec,sync,rw,noauto 0 0