starting tomcat via startup.sh fails with sudo -u myuser while running shell as user works

Question

sudo -u myuser sh /var/lib/tomcat6/bin/startup.sh 

fails while

sh /var/lib/tomcat6/bin/startup.sh 

as user myuser works

I try to run it as root user to start a service:

errors:

/usr/lib/jvm/java-6-openjdk/bin/java: 1: /usr/lib/jvm/java-6-openjdk/bin/java: ▒▒: not found
/usr/lib/jvm/java-6-openjdk/bin/java: 1: /usr/lib/jvm/java-6-openjdk/bin/java: ▒▒: not found
/usr/lib/jvm/java-6-openjdk/bin/java: 1: /usr/lib/jvm/java-6-openjdk/bin/java: ▒▒: not found
/usr/lib/jvm/java-6-openjdk/bin/java: 1: /usr/lib/jvm/java-6-openjdk/bin/java: cannot create 1@@8▒@8: Permission denied
/usr/lib/jvm/java-6-openjdk/bin/java: 1: /usr/lib/jvm/java-6-openjdk/bin/java:ELF: not found
/usr/lib/jvm/java-6-openjdk/bin/java: 2: /usr/lib/jvm/java-6-openjdk/bin/java: Syntax error: ")" unexpected