How to capture invalid Email address & hot of others things

After a long hiatus from writing in the blog, I am back;
Problem is that, it is difficult to decide whether the post will add value or is it something known to everyone, except me!

This was an interesting issue. What appeared to be a relatively straightforward work, stretched beyond 2 days with no end in sight.
There is a metalink note how to handle this 456378.1
However, this did not mention how to enable the Event - I did not see any way to enable. A little digging showed me that "Create Events" button has to be enabled. Enabled it myself using "FND: Diagnostics" option.
Once the oracle.apps.wf.notification.send.failure event was enabled, ensured that I created a malformed email address. Then created a test email by going to OAM->Workflow Manager -> Service Components -> "NotificationMailer"->View Details -> Test Email. selected my role and that is it. Now Oracle will generate an invalid email address or so I thought.
However, I found that the Notification was still in MAIL Status.
This led to question is the Background Engine on? I need to turn on the Background engine with all the three parameters as Y. No problem. But I need to know the Item type before I can start. Only problem is what is the Workflow Item Type? All I had was the Notification.
The Table WF_ITEM_TYPES_VL carries the Item_Type and is linked to WF_NOTIFICATIONS (WF_ITEM_TYPES_VL.NAME = WF_NOTIFICATIONS.MESSAGE_TYPE) .

I was able to see in the Mailer Log , that Workflow mailer has attempted to send a notification several times. all of them ended up with an error message: "451 Timeout waiting for client input"

How to Capture invalid email address?

How can invalid or mal-formed email address (or so called bouncing emails) be captured?

As note: 456378.1 says, after enabling the event WF_MAIL.Disable_Recipient_Ntf_Pref, if a recipient's email address is invalid, an email notification is sent out the SYSADMIN that an email notification could not be sent.
Note:
1. However, this will work only on or after RUP5.
2. Notification preference for SYSADMIN should be MAILHTML or MAIL

to read the complete metalink note, click here

How to display images in a seperate lines?

Pix 1:

I was trying to get two images displayed on a separate lines - although these are adjacent to each other; however to my exasperation, the images were displayed on the same lines. Have tried various tricks, including

. It is not consistent. For example these photos had to manually separated using text like this. Whereas, I was able to separate the technorati and LinkedIn icons. I will try to look at some examples later.
On a side note, these are the pictures of a bird that appeared outside our home, after I placed a toy bird - looks exactly like the one in the photo.

Pix 2: