This happens when the Enterprise Integration Manager (EIM) component's Component Event Configuration - SQL Tracing Event Type log level value is not set to 4.
Set the Component Event Configuration for the SQL Tracing Event Type to 4 in order to enable SQL tracing. For 7.0.x, the defaulted value is not 4, and need to be set explicitly.
For version 7:
It has a default value of 1, which means it only writes events of "severity" level of Informational (1) or more severe.
To set the Component Event Configuration, please follow the guidelines in Bookshelf Documentation for Siebel eBusiness Applications Version 7.0, Siebel Server Administration Guide, Chapter 4 Using the Server Manager GUI, Event Logging Administration, Configuring Component Events section:
1. Navigate to: View > Site Map > Server Administration > Components.
2. In the Server Components applet, select the Enterprise Integration Mgr server component.
3. Select the Component Event Configuration view tab.
4. In the Component Event Configuration list applet, select the event type SQL Tracing.
5. In the Log Level field, change the log level from 1 to 4
6. Step off the row to save changes.