$ echo $LD_LIBRARY_PATH
/home/almut/tmp/STAF/lib/:/usr/perl5/5.8.4/lib/sun4-solaris-64int/CORE

$ /usr/bin/perl -MPLSTAF -e1
ld.so.1: perl: fatal: relocation error: file /home/almut/tmp/STAF/lib//libPLSTAF.so: symbol Perl_Tstack_sp_ptr: referenced symbol not found

/home/almut/tmp/STAF/lib $ ldd -r libPLSTAF.so
        libpthread.so.1 =>       /lib/libpthread.so.1
        libsocket.so.1 =>        /lib/libsocket.so.1
        libresolv.so.2 =>        /lib/libresolv.so.2
        libSTAF.so =>    /home/almut/tmp/STAF/lib//libSTAF.so
        libperl.so =>    /usr/perl5/5.8.4/lib/sun4-solaris-64int/CORE/libperl.so
        libstdc++.so.2.10.0 =>   /home/almut/tmp/STAF/lib//libstdc++.so.2.10.0
        libm.so.1 =>     /lib/libm.so.1
        libnsl.so.1 =>   /lib/libnsl.so.1
        libc.so.1 =>     /lib/libc.so.1
        libdl.so.1 =>    /lib/libdl.so.1
        libm.so.2 =>     /lib/libm.so.2
        libmp.so.2 =>    /lib/libmp.so.2
        libmd5.so.1 =>   /lib/libmd5.so.1
        libscf.so.1 =>   /lib/libscf.so.1
        libdoor.so.1 =>  /lib/libdoor.so.1
        libuutil.so.1 =>         /lib/libuutil.so.1
        symbol not found: boot_DynaLoader               (./libPLSTAF.so)
        symbol not found: Perl_sys_init3                (./libPLSTAF.so)
        symbol not found: Perl_Tstack_sp_ptr            (./libPLSTAF.so)
        symbol not found: Perl_Tmarkstack_ptr_ptr               (./libPLSTAF.so)
        symbol not found: Perl_Tstack_base_ptr          (./libPLSTAF.so)
        symbol not found: Perl_croak_nocontext          (./libPLSTAF.so)
        symbol not found: Perl_Imodglobal_ptr           (./libPLSTAF.so)
        symbol not found: Perl_hv_common_key_len                (./libPLSTAF.so)
        symbol not found: Perl_sv_2uv_flags             (./libPLSTAF.so)
        symbol not found: Perl_Isv_yes_ptr              (./libPLSTAF.so)
        symbol not found: Perl_Ttmps_floor_ptr          (./libPLSTAF.so)
        symbol not found: Perl_Ttmps_ix_ptr             (./libPLSTAF.so)
        symbol not found: Perl_Tmarkstack_max_ptr               (./libPLSTAF.so)
        symbol not found: Perl_Ierrgv_ptr               (./libPLSTAF.so)
        symbol not found: Perl_TXpv_ptr         (./libPLSTAF.so)
        symbol not found: Perl_newSVpvf_nocontext               (./libPLSTAF.so)
        symbol not found: Perl_load_module_nocontext            (./libPLSTAF.so)
        symbol not found: Perl_Gthr_key_ptr             (./libPLSTAF.so)
        symbol not found: Perl_Iperl_destruct_level_ptr         (./libPLSTAF.so)
        symbol not found: Perl_Iexit_flags_ptr          (./libPLSTAF.so)
        symbol not found: Perl_Tstack_max_ptr           (./libPLSTAF.so)
        symbol not found: Perl_sv_2iv_flags             (./libPLSTAF.so)
        symbol not found: Perl_Top_ptr          (./libPLSTAF.so)
        symbol not found: Perl_Tcurpad_ptr              (./libPLSTAF.so)
        symbol not found: Perl_Isv_undef_ptr            (./libPLSTAF.so)
        /platform/SUNW,Sun-Blade-2500/lib/libc_psr.so.1
        /platform/SUNW,Sun-Blade-2500/lib/libmd5_psr.so.1

# confirmed by checking with nm, e.g.

$ nm -D ./libPLSTAF.so | grep Perl_Tstack_sp_ptr
[41]    |         0|       0|FUNC |GLOB |0    |UNDEF  |Perl_Tstack_sp_ptr

$ nm -D /usr/perl5/5.8.4/lib/sun4-solaris-64int/CORE/libperl.so | grep Perl_T