Problem with updating a WorkItem using Curl

Hi All,
I was using this useful guide: https://jazz.net/wiki/bin/view/Main/ResourceOrientedWorkItemAPIv2 to try to manipulate WorkItems from a script.
There is a section  regarding update of a Work Item:
https://jazz.net/wiki/bin/view/Main/ResourceOrientedWorkItemAPIv2#Update_a_Work_Item
The issue is that I always get

HTTP/1.1 412 Precondition FailedServer: Apache-Coyote/1.1Cache-Control: private, max-age=0, must-revalidateExpires: Wed, 20 Mar 2013 08:26:32 GMTVary: AcceptContent-Type: application/x-oslc-cm-change-request+json;charset=UTF-8Transfer-Encoding: chunkedDate: Wed, 20 Mar 2013 08:26:32 GMT{    "oslc_cm:message": "CRJAZ0007I Unable to update the item identified by \"https:\/\/clm-demo:9443\/ccm\/service\/com.ibm.team.repository.common.internal.IItemRestService\/itemName\/com.ibm.team.workitem.WorkItem\/90\" - there is a laterversion of this item available.",    "oslc_cm:status": 412}

and the update does not work.
I was running these commands:
set URL="https://clm-demo:9443/ccm/resource/itemName/com.ibm.team.workitem.WorkItem/90"
curl -D - -k  -b %COOKIES% -o "wi-90.json" -H "Accept: application/x-oslc-cm-changerequest+json" %URL%

And from the ETag response, run this line:

curl -D - -k -b %COOKIES% -H "If-Match: 7250960a-8438-31d1-a97a-5ffba71fc94e" -H "Content-Type: application/x-oslc-cm-change-request+json" -H "Accept: application/x-oslc-cm-change-request+json" -X PUT --data-binary @wi-90.json %URL%

and got the error above.
Any Ideas?
Thanks!
Asaf