Symptom:
ASDM does not save user-entered data within the textfield named ''Pre-login Page URL''.  This field exists within the ''External Portal Page'' Under ''Clientless SSLVPN 
Access''/Portal/Customization.

To reproduce, open ASDM and perform the following:
1. Go to ''Clientless SSLVPN Access''/Portal/Customization and ''Add'' new customization object
2. Select ''External Portal Page'', then check ''Enable External Portal''
3. Select ''HTML form auto-submit'' option, then click ''Set up URL''
4. Enter a value for ''Pre-login Page URL'', such as ''http://10.1.1.1''.  Then press OK
5. Click OK on the resulting External Portal Page.  Then click ''Apply''
6. On the new customization object you just created, click ''Edit''.
7. Click ''External Portal Page'' and then ''Edit URL''.
8. Notice the ''Pre-login Page URL'' textfield is cleared (not saved).

Conditions:
-Pre-login URL is entered via ASDM.
-This behavior exists in ASDM version 7.1(1)  on ASA code 9.1(1)