Yes and no; a VFX goof (the same kind that saw the Galaxy class starships in DS9 with their saucer-mounted impulse engines constantly lit), saw several Miranda class ships with the aft torpedo pods lit with the same glow as the impulse engines below it. What probably happened was the CG artist in charge of those shots thought the rollbar pod aft holes were impulse engines and lit them accordingly.
What this leaves is the fandom to decide whether or not they were ships modified to have extra sublight speed and maneuverability and thus have a very old design better able to keep up with more modern counterparts - the most popular theory. To devil's advocate it though, you COULD possibly say that those ships just had their aft torpedoes on hot standby as well, kinda like the TMP Klingon ships which had their tubes glowing before they fired. Who knows? Nothing was ever said in dialogue to support anyone modifying anything, after all.