SRF08, Hardware I2C on ATMega32, and delays

Has anyone on the list used the Hardware I2C on the mega parts to
communicate with the SRF08 sonar modules?  If so, have you ever had to
use a delay between reading the registers of one module, and another?  I
have to place a delay of like 200 or so nS between accesses of the
modules, or the I2C bus just seems to hang...  I do the delay with a
while(delay--); type dealie, so the delay depends on clock speed...

Do I really need this delay?  Am I doing something wrong, or has any one
else had the same issue?

Mike