R6k and Ethernet current

For the RCM67XX module, we've noticed an anomaly with current draw
when using Ethernet.

When the Ethernet port is connected to a LAN, the total current draw
for the computer section (motherboard + RCM67XX) is a steady 350ma.
However, if the Ethernet port is not connected, the current fluctuates
between 350ma and 500ma. We've traced the increase in current to the
call of pd_havelink() that occurs at about a 500ms rate. That 150ma of 
extra current seems like a huge increase just to check for a LAN 
connection. This pulsing current is affecting our ADC and DAC readings 
and settings.

This occurs on all of our modules. Anyone else notice this and/or have
any ideas on what to do about it? Adding extra bypass caps hasn't 
helped. 

Steve