Madeleine and Madeline can both be pronounced either MAD-uh-lin or MAD-uh-lien (lien = the same as the word "line"). The 'e' in Madeleine doesn't change the pronunciation. Check the list of pronunciations in the database, the "line" (lien) pronunciation is right there.
Right, it doesn't, but from my experience, people are more likely to pronounce Madeleine with the long "i" than they are to pronounce Madeline that way.