System.Data.SqlClient.SqlTransaction.ZombieCheck()

Hi Everyone,
This code is making me confuse
Is there a possibility that another Catch could execute after one Catch?, coz it seems like it is executing the Rollback more than once.

Code:
Catch ex As clsDatabaseException If Not IsNothing(dbtNumbers.Connection) Then dbtNumbers.Rollback() End If Throw New clsDatabaseException("clsImportBatch.vb [ProcessByScanningMode] - Data Access Exception", ex) Catch ex As clsBusinessException If Not IsNothing(dbtNumbers.Connection) Then dbtNumbers.Rollback() End If Throw New clsBusinessException("clsImportBatch.vb [ProcessByScanningMode] - Business Exception", ex) Catch ex As Exception If Not IsNothing(dbtNumbers.Connection) Then dbtNumbers.Rollback() End If Throw Ne ...