Just checked it and worked for me
Code as is using php 4.4.4
Code:
mystart = 20070305 ts = 1173016800
20070312 - 1173621600
20070319 - 1174226400
20070326 - 1174831200
20070402 - 1175436000
20070409 - 1176040800
20070416 - 1176645600
20070423 - 1177250400
20070430 - 1177855200
20070507 - 1178460000
20070514 - 1179064800
20070521 - 1179669600
20070528 - 1180274400
20070604 - 1180879200
20070611 - 1181484000
20070618 - 1182088800
20070625 - 1182693600