[BRLTTY] Configuration errors regarding brltty while compiling Orca

[Hermann]

Hi,
today I tried to install Orca. During the building procedure I got the 
following errors:
checking for brl... yes

checking for brlapi_initializeConnection in -lbrlapi... no
configure: WARNING: Could not find libbrlapi.so - you need BrlTTY >= 
3.7.2 and BrlAPI >= 0.4.1 installed to use braille

NOTE: This script was unable to find libbrlapi.so, which is needed
for braille device support.  Orca will continue to work fine without
braille support.  If you want to use braille, however, you must
install and run BrlTTY >= 3.7.2 and BrlAPI >= 0.4.1.

What do I have to install? I have brltty 3.7.2 running, include the 
package for brltty-x11.
Why is there no brlapi and where is that libbrlapi-library?
Regards
Hermann