language reverts to english on logoff

[torvista]

I have my development shop (upgraded to 1.38e) and a vanilla 1.38e on the same local xampp server.

After navigating in spanish and then logging off (all in classic template), the dev. shop always reverts to english, and the vanilla always stays in spanish, irrespective of the admin session cookie options.

"Obviously its a modified file somewhere".. well I have swapped out all the directories for vanilla ones, one by one and can't fix it.

The configure.phps are the same apart from the alias and cache directories.

I assume it is some cookie issue.

The web version of the dev shop works ok but I would like to know what is really going on if someone can point me in a likely direction,

thanks
Steve