do you have a public bug list?
files in .fmms/{push,mms} are owned by root... why?

some sugestion:
fmmsd (the mms daemon) only store the sms-push and send a alert of new mms ( i DO NOT want the fmmsd stop my internet connection to download a mms...it can be delayed... and in some country download a mms have a cost )

if i click on new mms alert => open the fmm_gui, conect to mms apn, download the mms, disconect from mms apn and show it

fmms_gui: intergrate to modest, show incoming mms { new, unread, not downloaded, read }, draft mms and send mms

fmms_send_gui: integrate to modest, add a option to choose a subject, make optional the resize, option for more of one file, multiples pages, etc

global: support mp3, avi, txt, etc..., autodetect my cell number, integrate fapn in fmms configuration, option to "share" to mms

and... very, very thanks for make the n900 support mms!!!