How to control Primary Menu links using Secondary Menu's Drupal 6?

I got a secondary menu with two items "English" & "Spanish" and Primary Menu with main site links.

We are not using Langauage transliation, we got separate records in database for each langauages.

So how can I make all Primary Menu links to select appropriate nodes(for each languages) when user select the secondary menu ?

That's is there any way to change the primary menu links while selecting the secondary menu ? or replace primary menu items using secondary menu ?

Please give me any info on this topic which can lead me to do this task !

That would take an awful lot of coding, you should use the transliteration module for this. If you don't you'll just end up rewriting a significant portion of that module just to get exactly the same functionality.

Don't reinvent the wheel, if a solution has already been made for your problem - use it!