Hi,
this one is failing:
concat(concat(concat(concat(Decode ( Length (Floor ( ([T_LOGIN] ) / 3600 ) ), 1,
concat('0',Floor (([T_LOGIN] ) / 3600 )), Floor (([T_LOGIN]) / 3600 ) ), ':'),
Decode ( Length ( Floor ( mod((([T_LOGIN] ) / 60), 60 ) ) ), 1,
concat( '0', Floor ( mod((([T_LOGIN]) / 60), 60 ))) ,
Floor (mod( (([T_LOGIN] ) / 60),60 ) ) )) , ':'),
Decode ( Length ( Round ( mod(mod(([T_LOGIN] ) ,60 ),60 ) )) , 1 ,
concat('0', Round (mod(mod(([T_LOGIN] ),60),60), 0)) , Round ( mod(mod(([T_LOGIN] ),60),60), 0) ))