Compile failure with --enable-async-io & solaris2.6

[Benjamin Brumaire]

I try to compile squid 2.1Patch2 with the option --enable-async-io on a
solaris26 machine.
As ggc2723 try to compile 
        gcc -g -O2 -Wall -D_REENTRANT -I. -I../include -I../include
-I/usr/include -c  aiops.c

I get this failures:

aiops.c: In function `aio_thread_loop':
aiops.c:207: `sigset_t' undeclared (first use this function)
        aiops.c:207: (Each undeclared identifier is reported only once
        aiops.c:207: for each function it appears in.)
        aiops.c:207: parse error before `new'
        aiops.c:215: warning: implicit declaration of function `sigemptyset'
        aiops.c:215: `new' undeclared (first use this function)
        aiops.c:216: warning: implicit declaration of function `sigaddset'
        aiops.c:229: warning: implicit declaration of function
`pthread_sigmask'

I look at signal.h and sys/signal.h under /usr/include. It seems fine to
me! 

Any idea?

thanks for any help

Benjamin Brumaire