multisampled fbo with rgba16f internal format

I’ve been trying to get multisampling to work with a rgba16f format. i’m using glRenderbufferStorageMultisample and blitting the fbos. I’ve got a color and depth attachments and don’t receive and errors but i get random white and black pixels popping up around the edges of the polys that are being multisampled. I can get everything to work flawlessly if i use rgba8 as the internal format when calling glRenderbufferStorageMultisample but as soon as i switch to rgba16f i get artifacts. I’ve tried multiple drivers and get the problem on both an 8800gts and a gt260 video cards. Been trying to fix this for months and have pretty much given up on multisampled hdr.