$ sudo port -f install MacPorts

[Charlse Darwin]

$ sudo port -fvd install MacPorts
DEBUG: Found port in file:///opt/local/var/macports/sources/ 
rsync.macports.org/release/ports/sysutils/MacPorts
DEBUG: Changing to port directory: /opt/local/var/macports/sources/ 
rsync.macports.org/release/ports/sysutils/MacPorts
DEBUG: Requested variant powerpc is not provided by port MacPorts.
DEBUG: Requested variant darwin is not provided by port MacPorts.
DEBUG: Requested variant macosx is not provided by port MacPorts.
DEBUG: Executing variant darwin_8 provides darwin_8
DEBUG: Executing variant darwin_8_powerpc provides darwin_8_powerpc
DEBUG: Skipping completed org.macports.main (MacPorts)
DEBUG: Skipping completed org.macports.fetch (MacPorts)
DEBUG: Skipping completed org.macports.checksum (MacPorts)
DEBUG: Skipping completed org.macports.extract (MacPorts)
DEBUG: Skipping completed org.macports.patch (MacPorts)
--->  Configuring MacPorts
DEBUG: Executing proc-pre-org.macports.configure-configure-0
DEBUG: Executing org.macports.configure (MacPorts)
DEBUG: Using compiler 'Mac OS X gcc 4.0'
DEBUG: Environment: CFLAGS='-O2 -isysroot /Developer/SDKs/ 
MacOSX10.4u.sdk -arch ppc -arch i386' CXXFLAGS='-O2' CPP='/usr/bin/ 
cpp-4.0' CXX='/usr/bin/g++-4.0' F90FLAGS='-O2' SHLIB_LDFLAGS='-Wl,- 
syslibroot,/Developer/SDKs/MacOSX10.4u.sdk -arch ppc -arch i386'  
OBJC='/usr/bin/gcc-4.0' FCFLAGS='-O2' INSTALL='/usr/bin/install'  
OBJCFLAGS='-O2' FFLAGS='-O2' CC='/usr/bin/gcc-4.0'
DEBUG: Assembled command: 'cd "/opt/local/var/macports/build/ 
_opt_local_var_macports_sources_rsync.macports.org_release_ports_sysutil 
s_MacPorts/work/MacPorts-1.6.0" && ./configure --prefix=/opt/local -- 
enable-readline'
configure: error: cannot run /bin/sh ./config.sub
Error: Target org.macports.configure returned: configure failure:  
shell command " cd "/opt/local/var/macports/build/ 
_opt_local_var_macports_sources_rsync.macports.org_release_ports_sysutil 
s_MacPorts/work/MacPorts-1.6.0" && ./configure --prefix=/opt/local -- 
enable-readline " returned error 1
Command output: configure: error: cannot run /bin/sh ./config.sub

Warning: the following items did not execute (for MacPorts):  
org.macports.activate org.macports.configure org.macports.build  
org.macports.destroot org.macports.install
Error: Status 1 encountered during processing.
$