FYI, if you're using 
conventional path for your exports with 
Oracle 8.1.7.3 or 8.1.7.4, be wary - there's a 
bug 
that could silently corrupt some data in your exports. 
 
 
According to Oracle: 
 
Versions Affected: 
8.1.7.3, 8.1.7.4, 9.0.1.2, 9.0.1.3, 9.0.1.4 
 
Versions NOT affected:  
8.1.7.0, 8.1.7.1, 8.1.7.2, 9.0.1.0, 9.0.1.1, 9.2.0.1 
 
 
There's a 
patch 
for this, but it sounds like the best workaround is to just always use 
direct path exports, which are faster anyway.