How Import data to DNN.

I have users from other portal, so I want create this users into DataBase sQL 2005,
the problem is that I have a UserId = 6 for example but into table "aspnet_Membership" that field is in other format
maybe encrypted. How introduce my UserId in this Field.

Or exist another form to load users inside the aplication???

Help me please

If it's not required to keep the old user IDs (instead let DNN assign them new IDs), and if you can export the old user data to XML, there's an .aspx page written by John Mitchell that can do the import. See his blog entry Bulk Import Users into DotNetNuke. The export/import process as a whole is a bit cumbersome, compared to commercial modules, but for a non-recurring job it's OK.