just to throw in my two cents worth...
i'm already communicating with slintz, but this isn't a problem specific only to him...the exact same thing happens to me when i try and spider my site...i always get between 10-15 seconds (sometimes up to 20) of delay / page
here is my server info:
OS: Solaris 5.8
PHP: 4.3.8
Apache: 2.0.50
MySQL: 4.0.13
PhpDig: 1.8.3
yes, i realize that some of those are older versions, but i have no control over that...i just write the webpages