From this discussion: https://groups.google.com/d/topic/liftweb/K14YPMlWNyY/discussion
I see what the issue is. SHtml.memoize is using the second stack frame as it's salt assuming that is the caller. Since SHtml is a singleton object though, there seems to be an extra frame involved. The stack trace looks like this.
I'll update it to use the following frame and submit on review board.
Updating tickets (#967, #990)
(In [[r:be68944d3374a9a5c9b180125a48499eb9ca781f]]) Changed the stack frame used as a RequestVar salt in SHtml.memoize so that it properly references the calling class
Imported from Assembla: http://www.assembla.com/spaces/liftweb/tickets/990
Changed the stack frame used as a RequestVar salt in SHtml.memoize so…
… that it properly references the calling class