Drupal dropdown translated order

Question

Drupal 7 plus Internationalization (won't list all modules as quite a lot!).

I have various dropdowns, including exposed view filters based on taxonomy references. These are all translated perfectly however they are always presented in the order of the taxonomy terms in the default language (English). The following shows what I mean, the English is in order but the Spanish appears in the English order

English    Spanish (as is)   Spanish (should be)
=======    ===============   ===================
bike       bici              bici
book       libro             coche
business   empresa           empresa
car        coche             libro

question is how to get the Spanish sorted in to alphanumeric order? (some of these dropdown have 30 or 40 items in a near random order and look awful!)

edit: incorrect additional information removed

Answer 1

rather embarrassingly I have just located a sort in my own code that causes the above behaviour! (Hangs head in shame and exits stage right)