openexr doesn't compiles with gcc 4.x.x because of a missing forward declaration. Here is patch to fix this.
Created attachment 65465 [details, diff] gcc4 patch The patch to make openexr 1.2.2 compile with gcc 4.
Created attachment 65466 [details, diff] Patch for openexr-1.2.2-r1.ebuild Here a trivial patch to include the patch. BTW, this patch is already applied to upstream CVS but who knows when a new version will be released...
done