How to update TerminalServicesProfilePath domain-wide?

OS = Server 2003 x86 SP1

PS = v 2.0

I need to find all users in our domain that have a TS User Profile and update the path to a new destination.  The problem is Get-ADUser cannot access the terminal services profile path.

I've been experimenting with the script below but I need to search the entire domain (not a specific user), test if the TerminalServicesProfilePath exists, then update it.

How do I loop the entire domain and test if a path value exists?

thx

function SetTSProperties()
{
 $ou = [adsi]"LDAP://ou=mytestou,dc=nwtraders,dc=com"
 $user = $ou.psbase.get_children().find($userDN)
 $user.psbase.invokeSet("allowLogon",1)
 $user.psbase.invokeSet("TerminalServicesHomeDirectory",$hDirValue)
 $user.psbase.invokeSet("TerminalServicesProfilePath",$ppValue)
 $user.psbase.invokeSet("TerminalServicesHomeDrive",$hdValue)
 $user.setinfo() 
} #end SetTSProperties

function QueryTSProperties()
{
 $ou = [adsi]"LDAP://ou=mytestou,dc=nwtraders,dc=com"
 $user = $ou.psbase.get_children().find($userDN)
 foreach($property in $aryTSProperties)
 {"$($Property) value: $($user.psbase.invokeget($Property))"
 } #end foreach
} #end QueryTSProperties

$userDN = "CN=My User"
$hDirValue = "\\Hamburg\TSUsers\Home\TestUser"
$hdValue = "t:"
$ppValue = "\\Hamburg\TSUsers\Profiles\TestUser"
$aryTSProperties="allowLogon","TerminalServicesHomeDirectory","TerminalServicesHomeDrive","TerminalServicesProfilePath"
SetTSProperties
queryTSProperties

from: http://blogs.technet.com/b/heyscriptingguy/archive/2008/10/23/how-can-i-edit-terminal-server-profiles-for-users-in-active-directory.aspx