APEX

With applogies in advace for a apex 101 guestion. I actually have tried to read the Customizing Templates chapter of the Users Guide. According to that guide, the folowing substitution strinrgs are supported in the the Error Template Control section of page templates.
#MESSAGE# and #ADDITIONAL_INFO# - Places the error message.
#TECHNICAL_INFO# - Displays detailed internal error information which will just be visible for developers.
#BACK_LINK# - Displays a link back to the previous page.
#OK# and #RETURN_TO_APPLICATION# - Returns to translated text strings.
However, if I enter the follow code

<p> message: &nbsp   #MESSAGE# </p>
<p> additional info: &nbsp #ADDITIONAL_INFO# </p>
<p> techie stuff: &nbsp   #TECHNICAL_INFO# </p>
<p> back link:  &nbsp  #BACK_LINK# </p>
<p> ok: &nbsp #OK# </p>
<p> return to application: &nbsp #RETURN_TO_APPLICATION# </p>

I get the following output:
message: ORA-02290: check constraint (WSFO_DATA.CC_OU_INTERNET_ACCESSIBILITY) violated
additional info:
techie stuff:
back link: javascript:window.history.go(-1)
ok: OK
return to application: Return to application.

It appears that only the first substitution string is doing anything. Would someone kindly (please be kind) what is going on here? I'm especially interested in additional info and technical info. The back_link just looks like an html snippet, not sure why I would use a substitution string for this. I imagine the last two could facilitate site translation, but that doesn't help much if there is no machinery for translating error messages thenselves.

Thanks,
Steve