It is not actually enforcing, as they can change it after the login. I have done it a while ago for Exodus properties file (xml) with a vbs script, can be applied to Spark:
Const ForReading = 1
Const ForWriting = 2
Set objFSO = CreateObject("Scripting.FileSystemObject")
Set objFolder = objFSO.GetFolder("E:\Admin\Exodus")
RepSubfolders objFolder
Sub RepSubFolders(Folder)
For Each Subfolder in Folder.SubFolders
Set objFile = objFSO.OpenTextFile(Subfolder & "\exodus.xml", ForReading)
strText = objFile.ReadAll
objFile.Close
strNewText = Replace(strText, "<server>192.168.12.41</server>", "<server>jiveserver</server>")
Set objFile = objFSO.OpenTextFile(Subfolder & "\exodus.xml", ForWriting)
objFile.WriteLine strNewText
objFile.Close
Set objFile = objFSO.OpenTextFile(Subfolder & "\exodus.xml", ForReading)
strText = objFile.ReadAll
objFile.Close
strNewText = Replace(strText, "<srv>false</srv>", "<srv>true</srv>")
Set objFile = objFSO.OpenTextFile(Subfolder & "\exodus.xml", ForWriting)
objFile.WriteLine strNewText
Next
End Sub