Sort Area Size (KB) - Invalid value for sort area size. The minimum value is: 96 KB

When I try to reorganize a tablespace with OEM 10g, I get an error in the 3rd step (option开发者_如何转开发s) saying : Invalid value for sort area size. The minimum value is 96 KB. My SGA management is set to AUTO. Why this error on sort size area ? Thanks for your help.

workarea_size_policy AUTO
pga_aggregate_target 8192 MB
large_pool_size 16777216 B
sort_area_size  65536

It is recommeneded to leave this parameter out. You are using AUTO and defined a very large PGA, let Oracle do it's magic!