pb compiling busybox with PAM

Hi,
I want to compile busybox with PAM(*). I have added linux-pam-dev in APKBUILD makedepends="linux-headers linux-pam-dev" which install also linux-pam for the building.
It fails at last linking phase with

/usr/lib/gcc/x86_64-alpine-linux-musl/4.9.2/../../../../x86_64-alpine-linux-musl/bin/ld: cannot find -lpam
/usr/lib/gcc/x86_64-alpine-linux-musl/4.9.2/../../../../x86_64-alpine-linux-musl/bin/ld: cannot find -lpam_misc

It fails the same even if linux-pam is installed

alpine-dev:~/aports/main/busybox$   find / -name libpam*
/lib/libpamc.so
/lib/libpamc.so.0
/lib/libpam.so
/lib/libpam.so.0
/lib/libpam_misc.so
/lib/libpam.so.0.83.1
/lib/libpamc.so.0.82.1
/lib/libpam_misc.so.0.82.0
/lib/libpam_misc.so.0

I found on some forums for other distros that maybe it is looking after a 32 bits version of the lib. But the machine is fresh x86_64 install.
I tried with arc="all" and arch="x86_64" for the same results...

Am I missing something obvious?
regards,

(*) I plan to use it with nss-pam-ldapd and pam_mkhomedir.