browser displaying ∫ instead of integral character

Hello all, I am creating a math element containing an equation on the
server side and when I output it as xml, I see ∫ instead of
the integral sign. It is the same thing with other character entities
too. Otherwise, everything is working.

I create the math element called math_element and display it as
follows:

<% Response.Write(math_element.xml) %>

I will appreciate it if anyone can provide a remedy for it.

Thanks,

DKM