Some other useful protocols can be found in the following references:
Caltuvetti et. al., 1993, J. Pathology 171:83 and Shi et. al., 1991 J. Hist. Cytochem. 39:741.
store at room temperature
Place the slides in a plastic coplin jar filled with denaturing solution and microwave on high for 5 minutes.
Change the denaturing solution and repeat, cool to room temperature.
Wash 5 times in PBS and proceed with staining as usual.