EF 4.3 Migration - how to produce a downgrade script?

I have an issue which I could not find answer for across the web.

I am using CodeFirst EF 4.3.1 Migrations with MsSQL.

I have added several migrations and now I want to produce a script for upgrade/downgrade between two migrations.

For upgrade I run the following command which successfully reproduces an upgrade script:

PM> Update-Database -Script -SourceMigration:"201205161144187_AddPostAbstract" -TargetMigration:"201205161203310_BlogLimitsAndTableRename"

However, for downgrade I run the following command which fails with the following error:

PM> Update-Database -Script -SourceMigration:"201205161203310_BlogLimitsAndTableRename" -TargetMigration:"201205161144187_AddPostAbstract"
Scripting the downgrade between two specified migrations is not supported.

Any ideas how can I generate a downgrade script?

Thanks.