Inter-org mailbox migration

[Killerbe]

Hi all,

I do not know if this is the correct spot here. But i want to use a powershell script along with an CSV to move my mailboxes between two forests (Consolidation).
I am no scripting wonder myself, so found the script using google (Barath) and adjusted it to fit my needs.

$Source = Get-Credential
$Target = Get-Credential 
Import-CSV MoveMailboxes.csv | foreach {Move-Mailbox -Identity $_.Username -TargetDatabase $_.TargetDatabase -SourceForestGlobalCatalog "DC.domain.local" -GlobalCatalog "DC.domain.local" -SourceForestCredential $Source -TargetForestCredential $Target -SourceMailboxCleanupOptions MailEnableSourceAccount}

And when i look at it, it should do what i expect from it.
But when i launch the script , it only prompts for the credentials.
And nothing else happens.
The CSV contains:

Username,"Exchangeserver\Storage Group\Mailbox database",
Username,"Exchangeserver\VIP storage group\VIP database",
Etc,Etc

When i do a manual move, it works

Move-Mailbox -Identity Username -TargetDatabase "ExchangeServer\Storage group\Mailbox Database" -SourceForestGlobalCatalog "DC.domain.local" -GlobalCatalog "DC.domain.local" -SourceForestCredential $Source -TargetForestCredential $Target -SourceMailboxCleanupOptions MailEnableSourceAccount

The csv is located in the same folder as the script, and the script is launched from the EMS (C:\Migration\Migmailbox.ps1). The operating system is Windows Server 2003, so there is no issue with elevation.

What am i doing wrong?