Have you ever noticed when you type "delete identity *" in the console, that "spadmin" doesn't get deleted.
This is because spadmin is marked as protected as shown here in the XML representation of spadmin's identity cube:
<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE Identity PUBLIC "sailpoint.dtd" "sailpoint.dtd">
<Identity created="1381136402786" id="ff808081419224c201419225096100c7" lastLogin="1381148428468" lastRefresh="1381149393598" modified="1381150980531" name="spadmin" password="1:p+qvPBo4Rig8PYlNWbr3Zg==" protected="true"/>
You can manually add this protected attribute to your XML or use the Java API to set this programmatically:
From the Java Docs, there are two methods:
public boolean isProtected()
Checks to see if the identity is protected.
public void setProtected(boolean b)
Can set the protected status of the Identity.