Same problem here.

I can delete any connection - yet when i get to the 2nd 3g connection the "delete" button is not accessable anymore.
And i also have this 2nd connection because of fmms & it never worked.
And i blame nokia - as - mms is one standard feature that simply must be available in a mobile.
I hardly ever use it - and still i DO need it SOMETIMES.
And sometimes does not go along with - not available at all.