Overflow Problem

1)In smart forms i am passing one structure .within that i am putting 3 component endda , begda .component type is dats.Then i need difference of this two.For this i declare one field diff.component type is int1.But in run time it gives me error OVERFLOW when converting.

2)In first time run -736410 is the value in overflow but i did not put any value like this. from where it is coming?

3)kindly give me the new link of posting a thread/question in this abap forum.if i am posting this in wrong location..