To set system-wide resources, add the resources to the file /etc/dt/config/language/sys.resources. (You may have to create the file.)
.dtprofile only supports /bin/sh or /bin/ksh syntax.
For example, if in /etc/dt/config/C/sys.resources you specify:
AnApplication*resource: value
then the resource AnApplication*resource will be
set in each user's RESOURCE_MANAGER
property at the next login.
To set personal resources, add the resources to the file HomeDirectory/.Xdefaults.