I kept looking for a while for the steps to change this, so I'm posting this so I can remember for next time.
General info on the script used is documented in MSDN:
These steps came from a user named Kent Weare on a BizTalk R2 General forum, but I am reposting his response in case it becomes unavailable in the future. The steps look to be copy-pasted from documentation somewhere, which I have yet to find an original source for. Note: there is no step 1.
Step 2: Retrieve the current BAMAlerts Application Definition File
1. On the Start menu, point to All Programs, point to Microsoft SQL Server 2005, point to Notification Services, and then click Notification Services Command Prompt to open a Notification Services Command Prompt window.
2. C:\Program Files\Microsoft BizTalk Server 2006\Tracking>cscript ProcessBamNSFiles.vbs -Get config.xml adf.xml
Step 3: Modify Application Definition File (ADF)
1. Copy adf.xml to ClusterAdf.xml
2. Change SMTP from info: from ‘BAM@Microsoft.com’ to ‘
4. Save ClusterAdf.xml
Step 4: Update the current BAMAlert Application Definition File (ADF)
1. C:\Program Files\Microsoft BizTalk Server 2006\Tracking>cscript ProcessBamNSFiles.vbs -Update config.xml ClusterAdf.xml
Don't worry about the "ClusterAdf.xml" naming convention. We clustered the Bam alerts service hence us calling the file that.