using a vbscript timer to change iframe source

I'm new to html and vbscript.

Here's my question:

I have a main page that has 3 IFrames. IFrame #1 handles the menu on the left. IFrame #2 changes when someone clicks a menu item.

IFrame #3. This is advertisements that I want to change which ad is showing based on a timer for the main page.

Looks like this:
________________
| | |
| | |
|____| |
| | |
|____|___________|

Everything works great except getting that iframe source to change.
Since I'm new, I'm extremely frustrated.

Any help would be appreciated. (Note: I'm using VBScript because I've coded in VB and it's easier for me.)

Regards,

Oh, well. the little picture didn't come out.
Sorry.

Just a thought..... If I can I stay away from M$ products. Now to get the gears moving..... Will your VB script work on FF? (I dont think so... ) So anyone without IE will have a little problem.

.02

If your trying to change the contents on the iframe...then
iframename.scr = "full path" has to be specified.

if u have placed a div on top of the iframe then u need to hide and unhide based on ur requirement.