Post-stratification abundance estimate incorrect

[erex]

Distance project to combine several strata into a single stratum. Created new field in stratum layer upon which to perform post-stratification.
e.g.
Strat1 (area 720) merged with Strat2 (area 372) merged with Strat3 (area 736). When abundance is calculated, the area of Strat1 is used, rather than the combined area of 3 strata.

This is a problem when post-stratifying, but of course, not when doing a 'normal stratification.'