There are some DBUS methods available for debugging.

run-standalone.sh dbus-send --print-reply --dest=com.nokia.modest /com/nokia/modest com.nokia.modest.DumpOperationQueue

(instead of DumpOperationQueue, you can also use DumpSendQueues or
DumpAccounts)

These methods will print a list of the current mail operation queue,
send queues or the accounts. If you don't know what that means, then
this problably not for you

"showui"
To actually start with the UI, you have to provide the 'showui' parameter to
modest. Reason for this not being the default is to allow for DBUS-activation
of various services without showing the UI.

"MODEST_DEBUG"
The MODEST_DEBUG environment may contain any number of ':'-separated strings
to trigger certain debugging features:


"abort-on-warning"
Abort the program when any Gtk/Glib warning or error occurs. This can be useful when running inside a debugger.

"debug-code"
Run various pieces of debug-only code in modest

"log-actions"
Log actions to the log file (not available yet)

"debug-objects"
Debug GObject usage (G_TYPE_DEBUG_OBJECTS)

"debug-signals"
Debug GSignal usage (G_TYPE_DEBUG_SIGNALS)

"factory-settings"
Return all the user-settings to the 'factory defaults'