Bash and "hogging" directories

[pesarif]

Hi,

I'm the type that mounts and unmounts entire filesystems (huge loopbacks 
mainly) regularly:

[root@tux /]# umount /usr/share/timidity
umount: /usr/share/timidity: device is busy

It is busy because bash has somehow "hogged" the directory because I had cd'ed 
into it (i.e. cd /usr/share/timidity):

bash       4746      joe  cwd    DIR        7,1     4096     98853 
/usr/share/timidity

Could you please prevent bash from "hogging" the directory or marking it as in 
use/busy?  Is it really neccessary to tell Linux that the directory is in use 
when all I have done is cd into it?

It would make unmounting (esp. floppies) a whole lot easier.

Thanks.