Answer
If you have Deployment Solution installed on the network to use your Package Server, then doing this would cause issues when trying to PXE boot due to SMB Signing issues.
Otherwise, it is still not recommended, as this will increase the network traffic load placed on your Domain Controller. Imagine a large package being downloaded from your Domain Controller by a number of Altiris Agents while at the same time your entire network is trying to get information and policies from your Domain Controller.
Because your Domain Controller is an essential piece of your network, and Package Servers require very little CPU and memory usage and only a large amount of disk space, it is recommended to find a separate computer1 you can configure to be a package server.