Sorting arrays

[Darth Cow]

I have this massive multikeyed array. I've loaded up arrays with the stats for various sites into $sites[$siteid], where $siteid is just a number to keep track of things. In there, I have set $sites[$siteid]["lastupdatetime"] for each (the time they were last updated, in seconds from 1970). I want to sort the various arrays in $sites[$siteid] by their respective values for $sites[$siteid]["lastupdatetime"], so I can just loop through $site[$siteid] and it'll be ordered right by date.

I'm kinda a PHP newbie (at least in some respects ), so I've tried looking at the PHP documentation for sort() and its varients, but I'm baffled by how to sort my massive array in the way I want .

Thanks in advance!