Wierd apache randomly accuring problem

I've installed a Linux server (RedHat 6.2)
and everything on it seem working fine DNS, sendmail and apache 1.3.23 with php 4.1.1,

But one thing is very wierd, that when browsing webpages on my server (which has several virtual hosts) the server randomly show page could not be found messages...

Most of the time it works fine, but when loading a webpage, (especially when it's the first time) apache says Page not found.. then when i Press refresh on my browser it' shows up.. some times I have to press several times refresh before it shows up!

anyone had similar problems before? I don't think it's a apache php related problem (i've compilde them myself in different ways with different versions and problem stays).. could it be something else interfering with the connection?

Usually one your browser have found the page it works fine.. it's just the first time it usually messes up..

Anyone know how I could solve this problem?
I would be very thankful!

D-Silence

Hard to tell without further details. If it has something to do with Apache, it could be the inappropriate use of Alias directive (without trailing slash).