isql hangs right while returning to unix shell

Hi, My isql hangs right before I hit last exit to return to unix shell. Sometimes it doesn't hang, sometimes hangs for a minute or two, sometimes much longer. Our applic. was also hanging similarly and we found that it hangs at this line: EXEC SQL disconnect default; A truss on the isql process showed that it hangs on a getmsg() call on /dev/tcp. Here are some relevant portions of it: ..... snip open("/dev/tcp", O_RDWR) = 6 ioctl(6, I_FIND, "timod") = 0 sigprocmask(SIG_BLOCK, 0xDFFFDC30, 0xDFFFDCE0) = 0 ioctl(6, I_PUSH, "timod") = 0 sigprocmask(SIG_SETMASK, 0xDFFFDCD0, 0xDFFFDCC0) = 0 ioctl(6, I_STR, 0xDFFFDAD8) = 0 sigprocmask(SIG_SETMASK, 0xDFFFDCC0, 0xDFFFDCA0) = 0 ..... snip read(0, 0x001626D4, 8192) = 0 write(6, "\\0 T\\0\\f", 4) = 4 getmsg(6, 0xDFFFEE14, 0xDFFFEE08, 0xDFFFEE84) = 0 write(6, "\\0 8", 2) = 2 getmsg(6, 0xDFFFEE74, 0xDFFFEE68, 0xDFFFEEE4) = 0 putmsg(6, 0xDFFFEDF8, 0x00000000, 0) = 0 ioctl(6, I_PEEK, 0xDFFFECBC) = 0 poll(0xDFFFEE30, 1, 100000) (sleeping...) -->> and hangs here. Informix says they can't find anything obvious. We have installed a solaris jumbo patch on our informix client system but no avail. We are running solaris2.4 with informix 7.13. We recently moved to a informix client/server setup and it is happening here. Previously it was all on one machine and never happened. Note that everything runs fine except for this problem. Any pointer is appreciated. Please cc me in your reply. Thanks. AH