Digital BW, The Print

I've been going back and forth between using the ABW mode and a
color-managed workflow for B&W prints.  The advantage to using a
color-managed workflow is that I find it much easier to tone images
using software, namely Lightroom and Photoshop.  

In OS X 10.4 (Tiger), I didn't notice a huge difference between the
ABW and color-managed version of the same print, if the paper profile
I was using is a good one.  However, since I upgraded to OS X 10.5
(Leopard), I notice a very big difference.  Unfortunately, they both
are imperfect.  

The ABW prints perfectly match what I see onscreen in terms of color
tonality, but they are significantly darker.  This was not an issue in
10.4.

The color-managed prints are a great match in terms of luminosity, but
they are noticeably cooler than what I see onscreen and have a
distinct blue/green cast.  Again, I didn't notice this in OS X 10.4.

I have calibrated my monitor twice since I upgraded to Leopard to two
different sets of targets: once to a color temp of 6500 & gamma of
2.2, and another time to the Apple LCD's "native color temp" and
"native gamma".  In both cases the problem persists.

I'm wondering if anyone has any thoughts or advice about how I might
troubleshoot this.  I'm afraid I'm at a bit of a loss here.