2 scripts don't work in the same page

[Mueretepronto]

1) Script Title: DHTML Tip Message

2) Script URL (on DD): http://www.dynamicdrive.com/dynamicindex5/popinfo.htm

3) Describe problem: trying to use in the same page two javascript:

DHTML Tip Message http://www.dynamicdrive.com/dynamicindex5/popinfo.htm

and

Jump to top Link http://www.dynamicdrive.com/dynamicindex5/jumptop.htm

"Tip message script" didn't work anymore after to include the "Jump to top link". IE shows the following error description:

---- IE msg ----
Line: 87
Char: 4
Error: 'lenght' null or not an object
Code: 0
URL: <my file>
---- end ----

There is a solution?

Thanks