Nested transaction and MSSQL problem

Hi, ALL

We have application that uses ADO 2.5 and Jet provider. In application have
lot of nested transactions. Now we must change database to MSSQL 7 and I get
exception that nested transactions is not supported. How we can solve this
problem without rewriting application (it more complex and must support MS
Access databases)? Whether ADO 2.6 supports nested transactions against
MSSQL 7.0?

TIA,

Miro.