What operating system are you using? The only OS's I know which support UEFI are OSX and some Linux varients - so YES, EEPC for Mac supports UEFI, and NO, there is no EEPC product for Linux.
None of the current Windows platforms will boot off a UEFI machine.
Per Wikipedia and MIcrosoft, UEFI is supported by several Windows 64-bit operating systems: Vista SP1, Windows 7, Windows Server 2008. The Dell Latitude 6510 laptop I am typing this on has UEFI. Good installation guides for 64-bit Windows start with making the decision whether to configure the platform for UEFI or legacy BIOS. If UEFI, the next decision is whether to use GUID Partiion Table (GPT) or legacy MBR partitioning on the boot disk.
Have you tried to get Win7 and below running on pure EFI? It's not a trivial thing at all. There's also minimal benefits as far as I can see outside the server world with huge disks.
If your quesion is does the current version of EEPC support pure eUFI, the answer is no - and no, it does not support GPT disks either. Win8 will be the first mainstream platform with this (Tiano) support.