Installing an ActiveX component on the palette in Delphi 4

I am trying to use the Adobe Acrobat  ActiveX control embedded in a
Delphi 4 application. When I had Acrobat version 3 installed on the PC
there was no problem. From the Component menu I chose the Install
ActiveX... item and there in the list of registered ActiveX components
was Acrobat Control for ActiveX (version 1.3). However the pdf.ocx
ActiveX that comes with Acrobat 5.0 is much more capable as it allows
you to hide the Acrobat tolbar and navigate to pages in code. I have
successfully installed the full version of Acrobat 5 and have tried
successfully to run regsvr32 .exe on the relevant pdf.ocx file, but I
cannot get it to appear in the list of ActiveX components that can be
installed on the Delphi palette. What am I doing wrong?
Barney Tyrwhitt-Drake