Update causing http 500 internal server error in admin

[TheHYPO]

I just did a big upgrade - basically going from 1.3.8 to 1.3.9h in effect. The storefront APPEARS to be working fine (haven't really tested heavily yet because of the other issue:) My admin section won't let me in.

I know 1.3.9h has the built-in debugger and what I've found is that the error (at this point) seems to be related to double-calling of functions. The error message is:

[07-Jan-2011 04:03:05] PHP Fatal error: Cannot redeclare zen_get_countries() (previously declared in /<<adminpath>>/includes/functions/general.php:785) in /<<basepath>>/includes/functions/functions_lookups.php on line 60

So in other words, a function zen_get_countries() is being called in both the admin general.php and in the storefront/non-admin functions_lookups.php.

Aside from these being separate areas of the store, the unedited 1.3.9h files both declare the function, and I don't think this is new to 1.3.9h. The 1.3.8a default files also both declare this function.

For interest, I commented out the one of the files and got a similar error with the next duplicated function:

[07-Jan-2011 04:18:08] PHP Fatal error: Cannot redeclare zen_get_country_name() (previously declared in /<<adminpath>>/includes/functions/general.php:336) in /<<basepath>>/includes/functions/functions_lookups.php on line 69

Can anyone advise me why zencart might be complaining now that I've done the update? Have I screwed something up? Please help me asap! my store is down until I figure this out!