Handling 'dynamic' parameter in ACS url

[Peter Schober]

* Cantor, Scott <cantor.2 at osu.edu> [2013-04-16 21:59]:
> If you wanted to enable the option to bypass that check globally, it
> isn't a terribly invasive patch, just a couple of lines of
> code. Most of the code changes are to make it a per-RP option and
> that would be a little more invasive to apply to a local copy.

Fyi, we've successfully used this code in the 2.3.x IdP for a while
(without the config option now added) to enable integration with an SP
which created dynamic ACS URLs on each SSO request (according to the
developers of that SP: to keep track of state).
The alternatives would very likely have been worse.

So if you'd rather run patched unofficial code than upgrade to a new
supported minor release you can find the patch in jira.
-peter