I wrote:
Once installed, the rewrite map can look like this:
RewriteEngine On RewriteMap urlencode int:ampencode
...
+static char *rewrite_mapfunc_ampescape(request_rec *r, char *key);
Err, make that "RewriteMap urlencode int:ampescape".
BTW, the code for rewrite_mapfunc_ampescape() is mainly ripped out of the URI-encoding function ap_os_escape_path() in main/util.c
-- brion vibber (brion @ pobox.com)