LEAP is a Cisco proprietary protocol developed by Cisco while the EAP standard was being finalized. There may be vendors that are building LEAP support into client software but for the most part, LEAP is Cisco. If you want a universal client standard, you probably want to look at EAP authentication. Your access point will have no problems passing this authentication to the server and Cisco Secure ACS for Windows does support EAP as well as LEAP.
Hope this helps...
Marcus