Script to find users created within 90 days

Hi Experts,

I ma trying to write a script to find all the users created within 90 days. In my environment powershell is disabled. Hence I have to go for ldap based queries.

I have tried the following dsquery command and there is no o/p. However there are many accounts created within 90 days.

dsquery * "dc=test,dc=contosso,dc=com" -filter "(&(objectcategory=person)(objectclass=user)(whencreated>=20151204000000.0z))"

As this to be run as a scheduled task, I have used a variable instead of 20151204000000.0z.

Thanks in advance,

Sajoor