How to specify automount options without /etc/fstab

[dg1727]

Hello, 

I have posted this same question on the Xfce forum just now:  

A user of mine has Xfce 4.8.3 (I believe - it's the default version 
that came with the distro) on Xubuntu 12.04.1 

I would like to set up his computer so that when any volume is 
about to be automounted, if the volume is ext4, then the volume is 
mounted with certain options specified by me.  Any other 
automounted volumes can be automounted according to the system 
defaults.  

I _don't_ want to use the conventional way of specifying volume 
label, block-device name, and/or mount point in the /etc/fstab 
file.  The volume in question will be connected by USB, and any of 
those 3 attributes of it may change.  

Would I have to replace "thunar-volman" with something else in 
order to modify the automounting process as I'm proposing?  Or is 
there a way to have a script intercept automounts before they get 
to "thunar-volman", whilst letting thunar-volman handle all 
automounts that my script doesn't handle?  

Thank you for any help.  

-dg1727