Error - Connection Problem

[rternier]

i've been modifying different parts of my site (attributes, products, categories etc.)
and all of a sudden i get this error message on my browser(While in the admin section):

0 DB_ERROR_NOT_CONNECTED
in:
[select * from project_version WHERE project_version_key = 'Zen-Cart Database' ]
If you were entering information, press the BACK button in your browser and re-check the information you had entered to be sure you left no blank fields.

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if I go to my main website, I get the:

This Is my store logo. [home link]
The site is currently down for maintenance. Please come back later.
Sorry!
There seems to be a problem connecting to our database. Please give us a few minutes to remedy the problem. Thank you.


To verify the site status ... Click here


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I installed "Stock By Attributes" module, and after that it worked for about 30 minutes... then it just shut down like this.

I can't for the life of me find an error file that shows in detail what is going on.

Any thoughts?

[rternier]

Ignore this. I had a problem earlier when my PHP sites were down... and the genious at my web hosting company changed my php version to 5...

<gets out his stupid stick>