While trying to find out where is the last login used saved, and why it comes blank if the software didn't exit normally, we found the following function:

public function string uf_busca_ultimo_login ();
//=======================================================
//	Function: 		uf_busca_login.
//	Returns: 	boolean  
//						True 	- operation carried out with success.
//						False	- operation with error.
//	Argument:	
//	Description:
//					Verifies if the user's login.
//=======================================================
String		ls_login

Select		LOGIN_USUARIO
Into		:ls_login
From		LOG_NAVEGACAO
Where	DT_LOG = (Select max(DT_LOG) from LOG_NAVEGACAO )
Using	Sqlca;

If Sqlca.SqlCode <> 0 Then
	ls_login 		= ''
Else
	// Adds 1 to the branch code
	If IsNull(ls_login) Then
		ls_login 		= ''
	End If
End If

Return ls_login



end function

(Comments have been translated for your enjoyment; any grammar errors on them were there in the original, except perhaps the "carried out" which was "realizada". DT_LOG is a DATE field.)