I rarely use Mac OS 9.x these days, and have never experienced the problem you described.
There is however, a workaround. Simply put the "Go" button on the Netscape Location Bar.
This screengrab of the Preferences for Mozilla 1.6 illustrates the workaround . . .
The "Go" button on Netscape 7.x and Mozilla works just like the "Go" button in IE.
Hope that helps in some way . . .
UserAgent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.6) Gecko/20040113
SeaMonkey = Swiss Army Knife: It's versatile, reliable, and contains useful tools.
Windows Internet Explorer = Old Swiss Cheese: Full of holes, and it stinks!