conflicting variants while rebuilding a dependency

[Riccardo Mottola]

Hi all!

I get this (Lion 10.7):

-->  Scanning binaries for linking errors
Could not open /opt/local/lib/libexiv2.26.dylib: Error opening or 
reading file (referenced from /opt/local/lib/libgexiv2.2.dylib)
--->  Found 1 broken file, matching files to ports
--->  Found 1 broken port, determining rebuild order
You can always run 'port rev-upgrade' again to fix errors.
The following ports will be rebuilt: gexiv2 @0.10.8+python27+python36
Continue? [Y/n]:
Error: boost: Variant python27 conflicts with python36
Error: Unable to open port: Error evaluating variants
Error: rev-upgrade failed: Error rebuilding gexiv2
Error: Follow https://guide.macports.org/#project.tickets to report a 
bug.


is this a "change" ? my current active port has indeed both variants:

The following ports are currently installed:
   gexiv2 @0.10.8_1+python27+python36 (active)

So, I suppose that when it was installed, the two python variants were 
possible, but now now anymore?

Riccardo