I have sucessfully compiled Stunnel 4.22 on Solaris 10, but still recieve the sam errors during the configure.
Initially I tried using Openssl-0.9.8f from Sun Freeware. Then I built and compiled Openssl-0.9.8g, but I still recieved the following errors on the build:
configure: **************************************** SSL
checking for SSL directory... /usr/local/ssl
checking for obsolete RSAref library... no
checking /usr/local/ssl/include/openssl/engine.h usability... yes
checking /usr/local/ssl/include/openssl/engine.h presence... no
configure: WARNING: /usr/local/ssl/include/openssl/engine.h: accepted by the compiler, rejected by the preprocessor!
configure: WARNING: /usr/local/ssl/include/openssl/engine.h: proceeding with the compiler's result
checking for /usr/local/ssl/include/openssl/engine.h... yes