It seems to be an error in the Module's recently added iterator feature, it's definitely worth filing a bug. I found that if I leave off the last argument to sunrise, I get an answer for that date.

($sunrise, $sunset)=sunrise($y,$m,$d,$long,$lati,$Zone,$DST,$ALT);

07:51
19:52
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That seems to be about three minutes off for both sunrise and sunset from what I get at this page: http://aa.usno.navy.mil/data/docs/RS_OneDay.php

Assuming that site is correct, it may still be close enough for your purposes.

Update: corrected some numbers above.