Users cannot enter details (SEF problem)

[netr]

Hi,

I have a client, and recently new users are not able to input their details for shipping info on a multilingual website. However, not all users have this problem - only the users having non-default language set (the default language is english, and with english everything works as expected).
The store has Virtuemart SEO and Joomla SEF enabled.

So to explain, a new user comes to the website (using non-default language). He/she puts some items into the shopping cart, and tries to checkout. When he/she clicks a button to enter their shipping info, it just redirects to the home page. If I turn on debug for all (in Virtuemart and Joomla), no errors are reported.

However, if I disable SEF, everything functions correctly.

The site has one menu item published (for each language), to the "shop". Also each language has one menu item to my-account (index.php?option=com_virtuemart&view=user&layout=edit). A joomla register module is also published and it works as expected. So people can register, but cannot enter their detail.

I researched this problem, and found many solutions which did not seem to work.

Joomla version 2.5.27
Virtuemart 2.0.26
php 5.2.17

Please help!
Cheers

[Milbo]

Update to vm2.6.28 or vm3.0.9

and your php version is outdated, you should use at least php 5.3