7 arguments passed to .Internal(identical) which requires 6

I know this has come up before on R-help
(http://r.789695.n4.nabble.com/7-arguments-passed-to-Internal-identical-which-

but I have a concise reproducible case that I wanted to share.

Also, please note the Bioconductor scenario which is potentially
seriously impacted by this.
The issue arises when a binary version of a package (like my example
package below) is built under R 2.15.0 Patched but then installed
under R 2.15.0.  Our package AnnotationDbi (which hundreds of other
packages depend on) is impacted by this issue to the extent that
calling virtually any function in it will return something like this:
Error in ls(2) :
  7 arguments passed to .Internal(identical) which requires 6

My concern is that when R 2.15.1 is released and Bioconductor starts
building all its packages under it, that R 2.15.0 users will start to
experience this problem. We can ask all users to upgrade to R 2.15.1
if we have to, but it's not usually the case that a minor point
release MUST be installed in order to run packages built under it
(please correct me if I'm wrong). We would much prefer a workaround or
fix to make an upgrade unnecessary.