the Boost ebuild lacks a 'unicode' USE-flag to enable compilation against ICU to use Unicode-aware regular expression. I'll attach a patch to the 1.33.1 ebuild that works for me.
Created attachment 92312 [details, diff] patch against boost-1.33.1.ebuild to add unicode USE-flag
How's this bug going? It's been 4 months and now it still remains unsolved. There seems no technical difficulty to achieve this. This support is common, for instance, Boost in FreeBSD/debian/ubuntu has already be configured with ICU regex unicode support.
As you can see, this bug depends on another one: I'm waiting for the ~x86-fbsd keyword on dev-libs/icu.
Fixed in CVS. I didn't do a revision bump, so please just set the "icu" USE-flag, resync and emerge. Thanks.