Invoke-command very slow

Hello,

I have a PS script with invoke-command.

I must use credssp, because I check from remote server an network share, if there is available.

This is my command:

			Invoke-Command 	-ComputerName 			$RemoteServer `
							-ScriptBlock 			$Script_Modify `
							-ConfigurationName 		Microsoft.PowerShell32 `
							-authentication			credssp `
							-Credential 			$credentials `
							-ErrorAction 			SilentlyContinue `
							-ArgumentList 			$To, $smtpServer, $test1,$Servername_org

This command takes 60 secounds, include network share check - double hop.

When I use command, whitout credssp, I can not use the network share check, but the script run very fast, maybe 5 secounds.

How can I speed up the credssp option?

Thanks Horst MOSS 2007 Farm; MOSS 2010 Farm; TFS 2010; IIS 7.5