Javascript onload question

So, I am attempting to use a third party application called eLayaway inside CSCart. I have communicated with both eLayaway and CSCart help desks and have basically been told that the two applications will not work together due to a jQuery conflict. However, We have reason to believe based on internal research that eLayaway is an important option to have available on our website. I have come up with a different option by creating the eLayaway button on the product page and then opening a new page with the onclick property and then using “body onload” to kick of the external javascript for eLayaway. This works great for Firefox. However, IE doesn’t work with the “body onload” property.

Any ideas or Javascript magic that anyone has would be helpful? You could check out the sources by viewing the following product page on my website and clicking on the eLayaway button:

[URL=“Outdoor Cooking - We're updating our site!”]Outdoor Cooking - We're updating our site!

It has to be opened in Firefox to see the eLayaway button since I have an IF statement causing it to not show up in IE.