get-childitem sort-object : how to sort by CreationDate

I am trying to get the functionality of cmd.exe's "dir /o:d" in PowerShell.
I have tried:

(gci . | ? { $_.PSIsContainer } | sort CreationDate)    

d----         1/15/2013  11:46 AM   
d----          3/5/2013   4:54 PM  
d----         1/15/2013  12:31 PM  
d----         5/10/2013  10:08 AM  
d----         5/17/2013   2:21 PM  
d----         5/15/2013  10:09 AM  
d----         5/15/2013   6:00 PM  
d----         4/15/2013   8:10 AM  

Similarly,

(gci . | ? { $_.PSIsContainer } | sort CreationTime)      

d----         1/15/2013  11:46 AM    
d----         1/15/2013  12:31 PM   
d----          3/5/2013   4:54 PM  
d----         5/15/2013   6:00 PM      
d----         5/15/2013  10:09 AM     
d----         5/10/2013  10:08 AM     
d----         5/17/2013   2:21 PM   
d----         4/15/2013   8:10 AM  

What am I missing to make the directory list sort by creation date?
TIA for any insights...