Error message

• Notice: Only variables should be passed by reference in eval() (line 4 of sites/all/modules/ds/ds.module(969) : eval()'d code).
• Notice: Only variables should be passed by reference in eval() (line 4 of sites/all/modules/ds/ds.module(969) : eval()'d code).
• Notice: Only variables should be passed by reference in eval() (line 4 of sites/all/modules/ds/ds.module(969) : eval()'d code).
• Notice: Only variables should be passed by reference in eval() (line 4 of sites/all/modules/ds/ds.module(969) : eval()'d code).
• Notice: Only variables should be passed by reference in eval() (line 4 of sites/all/modules/ds/ds.module(969) : eval()'d code).
• Notice: Only variables should be passed by reference in eval() (line 4 of sites/all/modules/ds/ds.module(969) : eval()'d code).
• Notice: Only variables should be passed by reference in eval() (line 4 of sites/all/modules/ds/ds.module(969) : eval()'d code).